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【327805】2023年贵州省中考数学真题

时间:2025-01-20 20:18:56 作者: 字数:21701字
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2023年贵州省中考数学真题

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一、选择题

1.5的绝对值是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
B
5
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

2.如图所示的几何体,从正面看,得到的平面图形是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    

3.据中国经济网资料显示,今年一季度全国居民人均可支配收入平稳增长,全国居民人均可支配收入为10870元.10870这个数用科学记数法表示正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

4.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> .若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的度数是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

5.化简 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 结果正确的是(       
A
1
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

6.石阡苔茶”是贵州十大名茶之一,在我国传统节日清明节前后,某茶叶经销商对甲、乙、丙、丁四种包装的苔茶(售价、利润均相同)在一段时间内的销售情况统计如下表,最终决定增加乙种包装苔茶的进货数量,影响经销商决策的统计量是(       

包装

销售量(盒)

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>


A
.中位数
B
.平均数
C
.众数
D
.方差

7.526日,“2023中国国际大数据产业博览会”在贵阳开幕,在“自动化立体库”中有许多几何元素,其中有一个等腰三角形模型(示意图如图所示),它的顶角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,腰长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则底边上的高是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>        
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

8.在学校科技宣传活动中,某科技活动小组将3个标有“北斗”,2个标有“天眼”,5个标有“高铁”的小球(除标记外其它都相同)放入盒中,小红从盒中随机摸出1个小球,并对小球标记的内容进行介绍,下列叙述正确的是(       
A
.摸出“北斗”小球的可能性最大
B
.摸出“天眼”小球的可能性最大
C
.摸出“高铁”小球的可能性最大
D
.摸出三种小球的可能性相同

9.《孙子算经》中有这样一道题,大意为:今有100头鹿,每户分一头鹿后,还有剩余,将剩下的鹿按每3户共分一头,恰好分完,问:有多少户人家?若设有x户人家,则下列方程正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

10.已知,二次数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的图象如图所示,则点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 所在的象限是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
A.第一象限
B
.第二象限
C
.第三象限
D
.第四象限

11.如图,在四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> .按下列步骤作图:①以点D为圆心,适当长度为半径画弧,分别交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> EF两点;②分别以点EF为圆心以大于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的长为半径画弧,两弧交于点P;③连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 并延长交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点G.则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的长是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
A2
B
3
C
4
D
5

12.今年“五一”假期,小星一家驾车前往黄果树旅游,在行驶过程中,汽车离黄果树景点的路程y <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> )与所用时间xh)之间的函数关系的图象如图所示,下列说法正确的是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
A.小星家离黄果树景点的路程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
B
.小星从家出发第1小时的平均速度为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
C
.小星从家出发2小时离景点的路程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
D
.小星从家到黄果树景点的时间共用了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

评卷人

得分




二、填空题

13.因式分解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> __________

14.如图,是贵阳市城市轨道交通运营部分示意图,以喷水池为原点,分别以正东、正北方向为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 轴、 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 轴的正方向建立平面直角坐标系,若贵阳北站的坐标是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则龙洞堡机场的坐标是_______
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>       

15.若一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 有两个相等的实数根,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的值是_______

16.如图,在矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 为矩形内一点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的面积是_______
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    

评卷人

得分




三、解答题

17.1)计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)已知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> .若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的取值范围.

18.为加强体育锻炼,某校体育兴趣小组,随机抽取部分学生,对他们在一周内体育锻炼的情况进行问卷调查,根据问卷结果,绘制成如下统计图.请根据相关信息,解答下列问题:

某校学生一周体育锻炼调查问卷


以下问题均为单选题,请根据实际情况填写(其中04表示大于等于0同时小于4
问题:你平均每周体育锻炼的时间大约是(       
A
04小时       B46小时
C
68小时       D8~小时及以上
问题2:你体育镀炼的动力是(       
E
.家长要求       F.学校要求
G
.自己主动       H.其他

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

(1)参与本次调查的学生共有_______人,选择“自己主动”体育锻炼的学生有_______人;
(2)
已知该校有2600名学生,若每周体育锻炼8小时以上(含8小时)可评为“运动之星”,请估计全校可评为“运动之星”的人数;
(3)
请写出一条你对同学体育锻炼的建议.

19.为推动乡村振兴,政府大力扶持小型企业.根据市场需求,某小型企业为加快生产速度,需要更新生产设备,更新设备后生产效率比更新前提高了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,设更新设备前每天生产x件产品.解答下列问题:
(1)
更新设备后每天生产_______件产品(用含x的式子表示);
(2)
更新设备前生产5000件产品比更新设备后生产6000件产品多用2天,求更新设备后每天生产多少件产品.

20.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> D,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,过点AD分别作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 相交于点E.下面是两位同学的对话:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

小星:由题目的已知条件,若连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则可
证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

小红:由题目的已知条件,若连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则可证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

(1)请你选择一位同学的说法,并进行证明;
(2)
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的长.

21.如图,在平面直角坐标系中,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是矩形,反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的图象分别与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,且点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的中点.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
(1)求反比例函数的表达式和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的坐标;
(2)
若一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的图象相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,当点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在反比例函数图象上 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 之间的部分时(点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 可与点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 重合),直接写出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的取值范围.

22.贵州旅游资源丰富.某景区为给游客提供更好的游览体验,拟在如图①景区内修建观光索道.设计示意图如图②所示,以山脚 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 为起点,沿途修建 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 两段长度相等的观光索道,最终到达山顶 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 处,中途设计了一段与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 平行的观光平台 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> .索道 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 与水平线夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 两处的水平距离 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,垂足为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> .(图中所有点都在同一平面内,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在同一水平线上)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>       
(1)求索道 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的长(结果精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> );
(2)
求水平距离 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的长(结果精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ).
(参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

23.如图,已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是等边三角形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的外接圆,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 并延长交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
(1)写出图中一个度数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的角:_______,图中与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 全等的三角形是_______
(2)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(3)
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,判断四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的形状,并说明理由.

24.如图①,是一座抛物线型拱桥,小星学习二次函数后,受到该图启示设计了一建筑物造型,它的截面图是抛物线的一部分(如图②所示),抛物线的顶点在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 处,对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 与水平线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 垂直, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在抛物线上,且点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 到对称轴的距离 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在抛物线上,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 到对称轴的距离是1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(1)
求抛物线的表达式;
(2)
如图②,为更加稳固,小星想在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上找一点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,加装拉杆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,同时使拉杆的长度之和最短,请你帮小星找到点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的位置并求出坐标;
(3)
为了造型更加美观,小星重新设计抛物线,其表达式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的值总大于等于9.求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的取值范围.

25.如图①,小红在学习了三角形相关知识后,对等腰直角三角形进行了探究,在等腰直角三角形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 作射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
(1)(动手操作)
如图②,若点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上,画出射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,并将射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 逆时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,根据题意在图中画出图形,图中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的度数为_______度;
(2)(
问题探究)
根据(1)所画图形,探究线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的数量关系,并说明理由;
(3)(
拓展延伸)
如图③,若点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上移动,将射线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 逆时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,探究线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 之间的数量关系,并说明理由.

参考答案

1.B

【解析】
正数的绝对值是它本身,由此可解.
解:5的绝对值是5
故选B

2.A

【解析】
根据从正面看得到的图象是主视图,可得答案.
解:从正面看,得到的平面图形是一个等腰梯形,
故选:A

3.B

【解析】
10870写成 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的形式,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> n为正整数.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故选:B

4.B

【解析】
根据“两直线平行,内错角相等”可直接得出答案.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故选B

5.A

【解析】
根据同分母分式加减运算法则进行计算即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,故A正确.
故选:A

6.C

【解析】
根据众数的意义结合题意即可得到乙的销量最好,要多进即可得到答案.
解:由表格可得,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,众数是乙,
故乙的销量最好,要多进,
故选C

7.B

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点D,根据等腰三角形的性质和三角形内角和定理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,再根据含30度角的直角三角形的性质即可得出答案.
解:如图,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> , <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故选B

8.C

【解析】
根据概率公式计算摸出三种小球的概率,即可得出答案.
解:盒中小球总量为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> (个),
摸出“北斗”小球的概率为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
摸出“天眼”小球的概率为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
摸出“高铁”小球的概率为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
因此摸出“高铁”小球的可能性最大.
故选C

9.C

【解析】
每户分一头鹿需x头鹿,每3户共分一头需 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 头鹿,一共分了100头鹿,由此列方程即可.
解:x户人家,每户分一头鹿需x头鹿,每3户共分一头需 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 头鹿,
由此可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故选C

10.D

【解析】
首先根据二次函数的图象及性质判断ab的符号,从而得出点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 所在象限.
解:由图可知二次函数的图象开口向上,对称轴在y轴右侧,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在第四象限,
故选D

11.A

【解析】
先根据作图过程判断 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,根据平行线的性质和角平分线的定义可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,进而可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,由此可解.
解:由作图过程可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故选A

12.D

【解析】
根据路程、速度、时间的关系,结合图象提供信息逐项判断即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,因此小星家离黄果树景点的路程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,故A选项错误,不合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,因此小星从家出发第1小时的平均速度为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,故B选项错误,不合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,因此小星从家出发2小时离景点的路程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,故C选项错误,不合题意;
小明离家1小时后的行驶速度为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,从家出发2小时离景点的路程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,还需要行驶1小时,因此小星从家到黄果树景点的时间共用了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,故D选项正确,符合题意;
故选D

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> = <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故答案为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
根据题意,一个方格代表一个单位,在方格中数出洞堡机场与喷水池的水平距离和垂直距离,再根据洞堡机场在平面直角坐标系的第三象限即可求解.
解:如图,以喷水池为原点,分别以正东、正北方向为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 轴、 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 轴的正方向建立平面直角坐标系,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 若贵阳北站的坐标是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 方格中一个小格代表一个单位,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>              
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 洞堡机场与喷水池的水平距离又9个单位长度,与喷水池的垂直距离又4个单位长度,且在平面直角坐标系的第三象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 龙洞堡机场的坐标是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
利用一元二次方程根的判别式求解即可.
解:∵关于x的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 有两个相等的实数根,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

16. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上截取 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,进而可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 为等腰直角三角形,则四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的面积 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,代入数据求解即可.
解:如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上截取 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的面积 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

17.14;(2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
1)先计算乘方和零次幂,再进行加减运算;
2)根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 列关于a的不等式,求出不等式的解集即可.
解:(1  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
移项,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
合并同类项,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
系数化为1,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的取值范围为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

18.(1)200122
(2)442

(3)
见解析

【解析】
1)先根据条形统计图求出参与调查的人数,再用参与调查的人数乘以选择“自己主动”体育锻炼的学生人数占比即可得到答案;
2)用2600乘以样本中每周体育锻炼8小时以上的人数占比即可得到答案;
3)从建议学生加强锻炼的角度出发进行描述即可.
1)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 人,
参与本次调查的学生共有200人,
选择“自己主动”体育锻炼的学生有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 人,
故答案为:200122
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 人,
估计全校可评为“运动之星”的人数为442人;
3)解:体育锻炼是强身健体的一个非常好的途径,只有有一个良好的身体状况,才能更好的把自己的精力投入到学习中,因此建议学生多多主动加强每周的体育锻炼时间.

19.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(2)125


【解析】
1)根据“更新设备后生产效率比更新前提高了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ”列代数式即可;
2)根据题意列分式方程,解方程即可.
1)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 更新设备前每天生产x件产品,更新设备后生产效率比更新前提高了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 更新设备后每天生产产品数量为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> (件),
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)解:由题意知: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
去分母,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
经检验, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是所列分式方程的解,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> (件),
因此更新设备后每天生产125件产品.

20.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
1)选择小星的说法,先证四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是平行四边形,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,再证明四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是矩形,即可得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ;选择小红的说法,根据四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是矩形,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,根据四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是平行四边形,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,即可证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,再用勾股定理解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 即可.
1)证明:①选择小星的说法,证明如下:
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的延长线上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
选择小红的说法,证明如下:
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
由①可知四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)解:如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

21.(1)反比例函数解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
1)根据矩形的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,再由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的中点得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,从而得到点E的纵坐标为2,利用待定系数法求出反比例函数解析式,进而求出点E的坐标即可;
2)求出直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 恰好经过D和恰好经过Em的值,即可得到答案.
1)解:∵四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
E的纵坐标为2
反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的图象分别与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
反比例函数解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)解:当直线  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 经过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
当直线  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 经过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的图象相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,当点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 在反比例函数图象上 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 之间的部分时(点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 可与点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 重合),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

22.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
1)根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的余玄直接求解即可得到答案;
2)根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 两段长度相等及 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 与水平线夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 求出C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的距离即可得到答案;
1)解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 两处的水平距离 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,索道 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 两段长度相等, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 与水平线夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    

23.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(2)
证明见详解;
(3)
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是菱形;

【解析】
1)根据外接圆得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的角平分线,即可得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的角,根据垂径定理得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,即可得到答案;
2)根据(1)得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,根据垂径定理得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,即可得到证明;
3)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是等边三角形,从而得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,即可得到证明;
1)解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是等边三角形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的外接圆,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的角平分线, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的角有: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的角平分线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)证明:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
3)解:连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 是菱形.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    

24.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

【解析】
1)设抛物线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 代入即可求解;
2)点B关于y轴的对称点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,求出直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> y轴的交点坐标即可;
3)分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 两种情况,根据最小值大于等于9列不等式,即可求解.
1)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 抛物线的对称轴与y轴重合,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 设抛物线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 抛物线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)解:  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 抛物线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 到对称轴的距离是1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
作点B关于y轴的对称点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> A共线时,拉杆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 长度之和最短,
设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 代入,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,位置如下图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
3)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 抛物线开口向下,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 范围内,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,y取最小值,最小值为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 范围内,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 时,y取最小值,最小值为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
综上可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 的取值范围为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>

25.(1)作图见解析;135
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ;理由见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ;理由见解析

【解析】
1)根据题意画图即可;先求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
2)根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> PBE四点共圆,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,根据等腰三角形的判定即可得出结论;
3)分两种情况,当点P在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上时,当点P在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 延长线上时,分别画出图形,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 之间的数量关系即可.
1)解:如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
故答案为:135
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ;理由如下:
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
根据旋转可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> PBE四点共圆,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
3)解:当点P在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 上时,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点F,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
根据解析(2)可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 为等腰直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 为等腰直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
当点P在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 延长线上时,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> ,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 于点F,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>    
根据旋转可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> BPE四点共圆,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a> 为等腰直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>
综上分析可知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/551/" title="贵州" class="c1" target="_blank">贵州</a> <a href="/tags/1022/" title="贵州省" class="c1" target="_blank">贵州省</a>