1 . 课本再现
如图,直线l垂直平分线段
,
,
,
,…是l上的点,分别量一量点
,
,
,…到点A与点B的距离,你有什么发现?可以发现,点
,
,
,…到点A的距离与它们到点B的距离分别相等.
定理证明
(1)为了证明该性质,珍珍画出了图形,并写出了“已知”和“求证”,请你完成证明过程.
已知:如图1,直线
,垂足为C,
,点P在直线l上,求证:
.
知识应用
(2)如图2,在
中,
,
,
分别是边
,
的垂直平分线,与
的交点分别为D,E,F,G,连接
,
,求
的周长.
如图,直线l垂直平分线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/11/84fe89cb-1a50-4b37-9b79-80dfe0867c57.png?resizew=161)
定理证明
(1)为了证明该性质,珍珍画出了图形,并写出了“已知”和“求证”,请你完成证明过程.
已知:如图1,直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5f56d4a08e50b95c1033c1ea3380c64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63e4d19bf237a6fca67e0d01a9ddb726.png)
知识应用
(2)如图2,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07140f277a35733d8c97577ccdd4e3ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/441dec590b47adc3678a291a3ec89a4a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/11/f9b3f394-09f5-4e40-ac07-792ff17e91c7.png?resizew=145)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/11/7a47ceef-9fb6-481a-8354-9fbb7e7778e7.png?resizew=145)
您最近一年使用:0次
2 . 在
中,
,M是边
的中点,
于点H,
平分
.
(1)求证:
平分
;
(2)过点M作
的垂线交
的延长线于点E,
①求证:
;
②
是什么三角形?证明你的猜想.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aed85a3f666c0736219766523c13cfc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d55963a9b9b02737110f57a377b41cb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fabb884dc5f9609de491245463bbe9a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/29/15c9f2e3-bb44-41e7-b940-4069932a8786.png?resizew=168)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5d0e7069ad7dab870bc7f78afb0e01.png)
(2)过点M作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
①求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ccc2bba2ab24022ce3ad33a6709da04.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/164a4df60a15587971e883cf557b5ce2.png)
您最近一年使用:0次
3 . 教材呈现:如图是华师版八年级上册数学教材第94页的部分内容.
2.线段垂直平分线
我们已经知道线段是轴对称图形,线段的垂直平分线是线段的对称轴.如图,直线
是线段
的垂直平分线,
是
上任一点,连结
、
.将线段
沿直线
对折,我们发现
与
完全重合.由此即有:
绕段垂直平分线的性质定理 线段垂直平分线上的点到线段两端的距离相等.
已知:如图,
,垂足为点
,
,点
是直线
上的任意一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/ecb988db-52e2-4aa9-a595-494355435bd1.jpg?resizew=96)
求证:
.
你写出完整的证明过程
分析
图中有两个直角三角形
和
,只要证明这两个三角形全等,便可证得
.
(1)请根据所给教材内容结合图①,写出“线段垂直平分线的性质定理”完整的证明过程.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/8349f47e-0274-4da7-89e9-1c5a300e8662.jpg?resizew=450)
定理应用:
(2)如图②,在
中,
、
的垂直平分线分别交
于点
、
,垂足分别为
,
,
,则
的周长为________.
(3)如图③,在
中,
,
,
、
分别是
、
上任意一点,若
,
的面积为30,则
的最小值是________.
2.线段垂直平分线
我们已经知道线段是轴对称图形,线段的垂直平分线是线段的对称轴.如图,直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
绕段垂直平分线的性质定理 线段垂直平分线上的点到线段两端的距离相等.
已知:如图,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f479d987bc7abd828c64f9dc745836ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/ecb988db-52e2-4aa9-a595-494355435bd1.jpg?resizew=96)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63e4d19bf237a6fca67e0d01a9ddb726.png)
你写出完整的证明过程
分析
图中有两个直角三角形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf4c26f3f4d96117f087400a0f32ece8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aeb5255e2159617505e0c87d01437a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63e4d19bf237a6fca67e0d01a9ddb726.png)
(1)请根据所给教材内容结合图①,写出“线段垂直平分线的性质定理”完整的证明过程.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/8349f47e-0274-4da7-89e9-1c5a300e8662.jpg?resizew=450)
定理应用:
(2)如图②,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3b8a4b0e72a4de1da975168b243a325.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
(3)如图③,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/305a88d4e0249bd16d48eda01331d2d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bb41f8ded9116e83f87a8e43b0ce7f8.png)
您最近一年使用:0次
名校
4 . 如图,在
中,点
,点
分别在
,
上,连接
,
,且
,
,
(1)尺规完成以下基本作图:作
的角平分线,交
于点
,交
延长线于点
(保留作图痕迹,不写作法,不写结论);
(2)在(1)问的条件下,连接
,求证:
.
请将下列证明过程补充完整.
证明:∵
平分
,
∴
(①________).
∵
,
,
∴②________,
(等腰三角形三线合一),
∴直线
是
的垂直平分线,
∴③________(线段垂直平分线上的点到这条线段两个端点的距离相等),
∴
(等边对等角).
∵
,
∴④________(两直线平行,同位角相等),
∴
(等量代换).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd95dc30c0344788b94289c464a3158e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d1e679d83e4675cdef9b81a62c53f21.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/29/464a8156-93f1-4625-b2af-cc610ada9e9f.png?resizew=180)
(1)尺规完成以下基本作图:作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3981e7286d41960daf4e110c1c84e03a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dea2ae9d515f9ab351ad72306b776ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
(2)在(1)问的条件下,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c13edd9cf3edfe787a5222e3b2ea29ef.png)
请将下列证明过程补充完整.
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3981e7286d41960daf4e110c1c84e03a.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff18ccdeabaa1490861fd56df99a1ba0.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd95dc30c0344788b94289c464a3158e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff18ccdeabaa1490861fd56df99a1ba0.png)
∴②________,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/761a77e11e1e45c2a8b2d34d22cf8e04.png)
∴直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
∴③________(线段垂直平分线上的点到这条线段两个端点的距离相等),
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18af9fb6892e7ef5ee2ec3986ac6036.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d1e679d83e4675cdef9b81a62c53f21.png)
∴④________(两直线平行,同位角相等),
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c13edd9cf3edfe787a5222e3b2ea29ef.png)
您最近一年使用:0次
2023-09-16更新
|
237次组卷
|
2卷引用:重庆市南开中学2023-2024学年八年级上学期开学考试数学试题
5 . 在学习完勾股定理后,喜欢思考的小明想进一步探究直角三角形斜边的中线,他的思路是:
在
中,先作出直角边
的垂直平分线,并猜测它与斜边
的交点是中点,于是他把交点与点
连接,通过垂直平分线的性质以及等角对等边的代换,他发现了直角三角形斜边的中线与斜边的数量关系.
请根据小明的思路完成以下作图 与填空 :
用直尺和圆规作
的垂直平分线交
与点
,垂足为点
,连接
.(保留作图痕迹,不写作法)
已知:在
中,
,
垂直平分
,垂足为点
.
求证:
.
证明:
垂直平分
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3e24c2bdad41127f07c6639a357d2b8.png)
① ,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/accb9dc1ba79e4195dd5699ee2855c57.png)
在
中,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
,
②
,
③ ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0574184df8079a4d1a45152cbb743da0.png)
.
.
通过探究,小明发现直角三角形均有此特征,请依照题意完成下面命题:
直角三角形斜边的中线 ④
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
请根据小明的思路完成以下
用直尺和圆规作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
已知:在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e3262fc038bbec5e7c8cc47df08bef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c71622531dfa894f21b2da123d020d24.png)
证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a50288ab167742c35976493d21531db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3e24c2bdad41127f07c6639a357d2b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6706fe00b4e231e62d9ecbec567d526b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/accb9dc1ba79e4195dd5699ee2855c57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16f3d198e76391779fa3badc848c8ac8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55f806322f1529fd8342d5778ebbebd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0ed48f47be746e2584e555478d5dfd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0c06422e1d55db3077257af113df4bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df629488364255d931d38ee81ce104db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0574184df8079a4d1a45152cbb743da0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffc824972f7280f5fbfad7cd05e749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e16718e16f2ada58db490f442b44401.png)
通过探究,小明发现直角三角形均有此特征,请依照题意完成下面命题:
直角三角形斜边的中线 ④
您最近一年使用:0次
6 . 【问题情境】
课外兴趣小组活动时,老师提出了如下问题:
如图①,
中,若
,
,求
边上的中线
的取值范围.
小明在组内经过合作交流,得到了如下的解决方法:延长
至点E.使
,连接
.请根据小明的方法思考:
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/21/78d6a65b-7cd7-4e97-8f44-cf42471bf49b.png?resizew=459)
(1)由已知和作图能得到
,依据是__________.
A.
B.
C.
D. ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5eb2decaa6be2df36a5e4b7fabf585d.png)
(2)由“三角形的三边关系”可求得
的取值范围是__________.
解后反思:题目中出现“中点”、“中线”等条件,可考虑延长中线构造全等三角形,把分散的已知条件和所求证的结论集中到同一个三角形之中.
(3)【方法应用】如图②,在四边形
中,
,点E是
的中点,若
是
的平分线,试猜想线段
、
、
之间的数量有关系,并证明你的猜想;
(4)【问题拓展】如图③,
中,
,
,
是
的中线,
,
,且
.直接写出
的长
__________.
课外兴趣小组活动时,老师提出了如下问题:
如图①,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54275b7e571660d0a9e0370fbfe5050b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1682d306c38087d9e6f7efb9cec596a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
小明在组内经过合作交流,得到了如下的解决方法:延长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ad98ad714864041a632ca949308e417.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/21/78d6a65b-7cd7-4e97-8f44-cf42471bf49b.png?resizew=459)
(1)由已知和作图能得到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82e101f2ad5cbdb169f866f0ea82f897.png)
A.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5a290f047f50481318d040c604d72f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6720e36b02193db161c61d4017673760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9beb8b968744573e593ac28451c69729.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5eb2decaa6be2df36a5e4b7fabf585d.png)
(2)由“三角形的三边关系”可求得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
解后反思:题目中出现“中点”、“中线”等条件,可考虑延长中线构造全等三角形,把分散的已知条件和所求证的结论集中到同一个三角形之中.
(3)【方法应用】如图②,在四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2947ca8e0cdbeb4aab80ce9e7b63ba98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
(4)【问题拓展】如图③,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60d9142db4dd2ef151bf3d4a63afb61e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/531d6f90f144551a35d494b1fe7d2b89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8832c5450a61500ccbf73d95e16f449.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb64353c99068a7a1a8508a22f5b25b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6706fe00b4e231e62d9ecbec567d526b.png)
您最近一年使用:0次
2024-01-20更新
|
84次组卷
|
2卷引用:广东省惠州市尚书学校2023-2024学年九年级上学期期末数学试题
7 . 【教材呈现】下图是华师版数学教材八年级下册第
页的部分内容
请根据教材分析,结合图
,写出完整的证明过程
证明 【结论应用】如图
,直线
分别交矩形
的边
于点
,将矩形
沿
翻折,使点
与点
重合,点
落到点
处,若
,
,则矩形
的面积为________.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/14/e04d7fd8-807c-468b-a75b-15d57fdefbc6.png?resizew=448)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c2ec887d7dd700df4dc1634d09865be.png)
例![]() ![]() ![]() ![]() ![]() ![]() ![]() 分析 要证四边形 ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e1c9ae241fd78126274c65e17990c88.png)
证明 【结论应用】如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c650fe55b7603f106c53ca2423451c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ba48366317ebea1c9dd5e4e67e03092.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cf9b288c48c73463a2f214f02b6952a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5b3bd5e6bc2a0a277d279bb01af9584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f21d8e7af78693e5da7957c8034e8bcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83a21f10cb259b56414494eb209d767f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/14/e04d7fd8-807c-468b-a75b-15d57fdefbc6.png?resizew=448)
图① 图②
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名校
8 . 如图,
中,
, ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2457c9087070840f4a2ec177cbb676f8.png)
(1)尺规作图:作
边的垂直平分线
交
于点
,交
于点
.(保留作图痕迹,不要求写作法和证明);
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ef14126f9e6feefa2743f73557aedb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2457c9087070840f4a2ec177cbb676f8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/22/b7d119b4-8a8f-44be-b63f-bd941df44573.png?resizew=146)
(1)尺规作图:作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a6c6e7c025362c46a64a8956761f08e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a9c6a736e6eac98a676fa3232db5a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681b593dba5d76f3de43e8dd41a13fc8.png)
您最近一年使用:0次
2023-08-19更新
|
111次组卷
|
6卷引用:2023年广东省万阅百校联考中考质检数学试卷
9 . 如图,
是矩形
的对角线.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/9c0f16d5-69d5-4c1f-92c3-fa23070a0898.png?resizew=143)
(1)作
的垂直平分线
交
于点E,交
于点F(尺规作图,保留作图痕迹,不写作法和证明);
(2)在(1)所作的图形中,连接
,求证:四边形
是菱形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/9c0f16d5-69d5-4c1f-92c3-fa23070a0898.png?resizew=143)
(1)作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167593eea25543e3b3c6f60e209e9b73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)在(1)所作的图形中,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fbe3114e3904346f34ffa843cbb3146.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/910936ec9fb419d51ce2f5ea817f8401.png)
您最近一年使用:0次
名校
10 . 教材呈现:如图是华师版八年级上册数学教材第94页的部分内容.
请根据所给教材内容,结合图①,写出“线段垂直平分线的性质定理”完整的证明过程.
定理应用:
(1)如图②,在
中,
、
的垂直平分线分别交
于点
、
,垂足分别为
,
,已知
的周长为20,则
的长为__________.
(2)如图③,在
中,
,
,
、
分别是
、
上任意一点,若
,
,
,则
的最小值是__________.
2.线段垂直平分线 我们已经知道线段是轴对称图形,线段的垂直平分线是线段的对称轴.如图13.5.1,直线 ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() 线段垂直平分线的性质定理 线段垂直平分线上的点到线段两端的距离相等. 已知:如图13.5.1, ![]() ![]() ![]() ![]() ![]() ![]() 分析 图中有两个直角三角形 ![]() ![]() ![]() |
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/20/449e0f3e-25f0-4b06-ba6d-cf363eed0870.png?resizew=741)
请根据所给教材内容,结合图①,写出“线段垂直平分线的性质定理”完整的证明过程.
定理应用:
(1)如图②,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)如图③,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b939af5ba06e279cce39396aaf0fae06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc34db5860990e51ba31edc8cdd077c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04ee826937d2add7a93aaa1422f8b736.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bb41f8ded9116e83f87a8e43b0ce7f8.png)
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