1 . 如图,已知:AB=AC,AD=AE,∠1=∠2,求证:∠B=∠C.
![](https://img.xkw.com/dksih/QBM/2021/11/7/2846072100601856/2902002150129664/STEM/3ca3f852ea4a440998be6fe2ffc59339.png?resizew=136)
证明:∵∠1=∠2(已知),
∴∠1+ =∠2+ (等式的性质).
即∠BAD= .
在△ABD和△ACE中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe726658abba95c1b5a009f6b4c99e19.png)
∴△ABD≌△ACE( ),
∴∠B=∠C( ).
![](https://img.xkw.com/dksih/QBM/2021/11/7/2846072100601856/2902002150129664/STEM/3ca3f852ea4a440998be6fe2ffc59339.png?resizew=136)
证明:∵∠1=∠2(已知),
∴∠1+ =∠2+ (等式的性质).
即∠BAD= .
在△ABD和△ACE中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe726658abba95c1b5a009f6b4c99e19.png)
∴△ABD≌△ACE( ),
∴∠B=∠C( ).
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2 . 求证:全等三角形对应边上的中线相等.
要求:①根据给出的
ABC及线段
(
=AB),以线段AB为一边,在给出的图形上用尺规作出
,使得
≌
ABC,不写作法,保留作图痕迹;②在已有的图形上画出一组对应边上的中线,并据此写出已知、求证和证明过程.
要求:①根据给出的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb0628cecbfc98d390e5447d52414e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb0628cecbfc98d390e5447d52414e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8ee6e1d480ece7117e1f87ebf4bbeea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8ee6e1d480ece7117e1f87ebf4bbeea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/83392351-12f6-44db-90a5-bd0c74e72338.png?resizew=291)
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2卷引用:福建省福州市鼓楼区福州杨桥中学2021-2022学年八年级上学期期中数学试题
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3 . 如图,等腰直角
中,
,点
,
在
上,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/21/61b6d800-19dd-40c0-b3f0-b1b8f8129d22.png?resizew=132)
(1)将
绕点
逆时针旋转
,点
对应点为点
,画出旋转后的图形,并证明:
;
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b10134e7a46e6f6f7cb9d5e2371727d.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a1af32e267e35ef79bcb8df5d169283.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/21/61b6d800-19dd-40c0-b3f0-b1b8f8129d22.png?resizew=132)
(1)将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fe6d389a6c448d92b79d89bc9e8489f.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff765b7e9efd4b044823c4a6c787a811.png)
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4 . 已知:在
中,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4354365ca0929f8a606ed0bf341e4ca.png)
证明:如图,作______
在
和
中,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f78214a2e095752f6b3e4bf49eb146.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8710974add1e6f9936fdf504e4faab2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bda281982119ab3bdc8abfc05ad2f5a.png)
其中,横线应补充的条件是( )
![](https://img.xkw.com/dksih/QBM/2021/4/24/2706666699587584/2709095986839552/STEM/d2a875a5-1ccc-41bb-ba9e-ab5d57780bc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4354365ca0929f8a606ed0bf341e4ca.png)
证明:如图,作______
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f78214a2e095752f6b3e4bf49eb146.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8710974add1e6f9936fdf504e4faab2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bda281982119ab3bdc8abfc05ad2f5a.png)
其中,横线应补充的条件是( )
![](https://img.xkw.com/dksih/QBM/2021/4/24/2706666699587584/2709095986839552/STEM/d2a875a5-1ccc-41bb-ba9e-ab5d57780bc8.png)
A.![]() ![]() | B.![]() ![]() |
C.![]() ![]() | D.![]() |
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4卷引用:2021年河北省邢台市初中毕业升学文化课模拟考试九年级数学试题(一)
2021年河北省邢台市初中毕业升学文化课模拟考试九年级数学试题(一)2021年河北省邢台市桥西区中考一模数学试题(已下线)1.3 全等三角形的判定(SAS)(培优分阶练)-2022-2023学年八年级数学上册课后培优分级练(苏科版)江苏省徐州市第十三中学2023-2024学年八年级上学期期中数学复习提升试题
5 . 如图,将平行四边形
的边
延长到点E,使
,连接
,交边
于点F.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/28/d458bf2a-1e39-4818-a7a1-b5445c5f279b.png?resizew=173)
(1)求证:
.
(2)连接
、
,若
,判断四边形
的形状并证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e92f48e9bfe12d145f7d2a2f0360d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/28/d458bf2a-1e39-4818-a7a1-b5445c5f279b.png?resizew=173)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1c558c34012f593801a396f8c928fc2.png)
(2)连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc602211e933dde83db55722e1268ed9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adfe2a58326612fcabd34fd4402a66ee.png)
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6 . 如图1,在
中,
,点D是直线BC上一点(不与点BC重合),以AD为一边在AD的右侧作
,使
,
,连接CE.设
,
.
(1)求证:
.
(2)当点D在线段BC上运动时,
①
,则
________
.
②猜想
与
之间的数量关系,并对你的结论进行证明
(3)如图2,当点D在线段BC的反向延长线上运动时,猜想
与
之间的数量关系,并对你的结论给出证明.
![](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/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43651721f6c0ea4cf50a33054ecc5d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb2cf0e95fdf1fd8a5b01d3dfd905e08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d80bb35aee114b8467fdc10a2cab02ad.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97ee10d27038214b1c255de8a0e348c6.png)
(2)当点D在线段BC上运动时,
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51af2577e349157f70effa2a074c9c23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90ca3f0a4b2d06539e74594736881aaa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83873a9d782f2588c5eedbfe73f9bc2f.png)
②猜想
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
(3)如图2,当点D在线段BC的反向延长线上运动时,猜想
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://img.xkw.com/dksih/QBM/2021/1/7/2631170971557888/2634564647084032/STEM/b4070502-9b03-4bcc-a9fb-0008e0b49b76.png)
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3卷引用:广东省汕头市潮阳区铜盂镇2020-2021学年八年级上学期期末数学试题
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7 . 证明命题:如果两个锐角三角形有两边和其中一边上的高分别对应相等,那么这两个三角形全等.
(1)画出图形,写出已知,求证.
(2)写出证明过程.
(1)画出图形,写出已知,求证.
(2)写出证明过程.
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6卷引用:福建省夏门双十中学2020~2021学年八年级上学期第一次月考数学试题
解题方法
8 . 如图,图1等腰△BAC与等腰△DEC,共点于C,且∠BCA=∠ECD,连结BE、AD,若BC=AC、EC=DC.
(1)求证:BE=AD;
(2)若将等腰△DEC绕点C旋转至图2、3、4情况时,其余条件不变,BE与AD还相等吗?为什么?(请你用图2证明你的猜想)
(1)求证:BE=AD;
(2)若将等腰△DEC绕点C旋转至图2、3、4情况时,其余条件不变,BE与AD还相等吗?为什么?(请你用图2证明你的猜想)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/14/21dda1b3-55ea-4692-9148-9d4bcc7f8f1c.png?resizew=584)
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5卷引用:四川省广元市普安中学校2020-2021学年八年级上学期第一次月考数学试题
四川省广元市普安中学校2020-2021学年八年级上学期第一次月考数学试题(已下线)专题12.26 三角形全等几何模型-旋转模型(专项练习)-2022-2023学年八年级数学上册基础知识专项讲练(人教版)(已下线)专题1.53 全等三角形几何模型-旋转模型(专项练习)-2022-2023学年八年级数学上册基础知识专项讲练(浙教版)(已下线)专题08 旋转模型证全等-【微专题】2022-2023学年八年级数学上册常考点微专题提分精练(浙教版)(已下线)专题4.21 三角形全等几何模型(旋转模型)(培优练)-2023-2024学年七年级数学下册基础知识专项突破讲与练(北师大版)
9 . 阅读下面材料,完成任务.
三角形中位线定理
连结三角形两边中点的线段叫做三角形的中位线.关于中位线有如下定理:三角形的中位线平行于第三边,并且等于第三边的一半.如图①,在
中,
,
分别是
,
的中点.(
是
的一条中位线)则有
,
.
下面是该定理的部分证明过程:如图②延长
至点
,使
,连结
,
……
任务:
(1)请按照上面的思路,写出该证明的剩余部分.
(2)已知:如图③,在
中,
,
,
.
求证:
、
互相平分.
三角形中位线定理
连结三角形两边中点的线段叫做三角形的中位线.关于中位线有如下定理:三角形的中位线平行于第三边,并且等于第三边的一半.如图①,在
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e210c9698063925ad2df6b6c1749571.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/950e82a0f9712457f2dd9f8a93f8a217.png)
下面是该定理的部分证明过程:如图②延长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9a9618018d717926540d1452f76e44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/735056c174e8dd7906257a2a50a962a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d3971a9519246550390de4bd599617d.png)
任务:
(1)请按照上面的思路,写出该证明的剩余部分.
(2)已知:如图③,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f855c80172c04310d342f82d960011ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/104cacf19f1897c6c86d24c5fe8cb991.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee5b4b37387afff224ccf309fb2f1c3.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/21/66af5212-27be-4fd1-8e26-d029bbc8024b.png?resizew=443)
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3卷引用:山西省晋城高平市2019-2020学年八年级下学期期末考试数学试题
山西省晋城高平市2019-2020学年八年级下学期期末考试数学试题(已下线)易错17 三角形中位线易错-2020-2021学年八年级数学下册期末突破易错挑战满分(北师大版)第五章 平行四边形 3 三角形的中位线鲁教版八年级上册课后作业
名校
10 . 教材呈现:下图是华师版八年级上册数学教材第94页的部分内容.
定理证明:请根据教材中的分析,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,直线
分别是边
的垂直平分线,直线m、n交于点
,过点
作
于点
.
求证:
.
(2)如图③,在
中,
,边
的垂直平分线交
于点
,边
的垂直平分线交
于点
.若
,则
的长为__________.
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 ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() 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, ![]() ![]() ![]() ![]() 求证: ![]() ![]() ![]() ![]() |
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/0877194ab8760f54c35527177b03ff93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/887721a843b2dc8e947cc42d09868e33.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efeccd375f7ee16b46cc1f5c22d1995f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d03a6074fa932d98728d6d61670aea7.png)
(2)如图③,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.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/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2822068234707f3d9840cbac6eca592.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
您最近一年使用:0次
2020-12-24更新
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245次组卷
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2卷引用:吉林省长春市宽城区2019-2020学年八年级上学期期末数学试题