如图,在
ABC中,AB=BC,∠ABC>90°,E、D分别为线段AB、射线CB上两点,且AE=DE,EF
BC交AC于F,FG
DE交直线BC于G.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/30/2199ae50-285f-4008-8928-1a41159f7eef.png?resizew=696)
(1)求证:四边形DEFG为菱形;
(2)过F作FM⊥BC交于M,且GM=3,FM=4,N为EB中点,连接MN.
①如图2,若点B与点G重合,求MN的长;
②当N恰好在四边形DEFG的边上时,请直接写出MN的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/30/2199ae50-285f-4008-8928-1a41159f7eef.png?resizew=696)
(1)求证:四边形DEFG为菱形;
(2)过F作FM⊥BC交于M,且GM=3,FM=4,N为EB中点,连接MN.
①如图2,若点B与点G重合,求MN的长;
②当N恰好在四边形DEFG的边上时,请直接写出MN的长.
更新时间:2021-08-19 19:40:18
|
相似题推荐
解答题-证明题
|
较难
(0.4)
名校
【推荐1】如图,在
中,点
是边
的中点,连接
并延长,交
的延长线于点
,连接
、
.
![](https://img.xkw.com/dksih/QBM/2021/9/9/2804599418290176/2810937245851648/STEM/de7d5c4efbc64905bda768af714b3339.png?resizew=249)
![](https://img.xkw.com/dksih/QBM/2021/9/9/2804599418290176/2810937245851648/STEM/9878e0fe89d14337a5de48714409b2cb.png?resizew=234)
![](https://img.xkw.com/dksih/QBM/2021/9/9/2804599418290176/2810937245851648/STEM/9878e0fe89d14337a5de48714409b2cb.png?resizew=234)
(1)求证:四边形
是平行四边形;
(2)请在图
中用一把无刻度的直尺画出
边的中点
(保留画图痕迹,无需证明过程);
(3)若
,
,
,动点
从点
出发,以每秒
个单位的速度沿
向终点
运动,设点
运动的时间为
秒.
①若点
为直线
上的一点,当
运动时间
为何值时,以
、
、
、
构成的四边形
可以是菱形?
②在点
运动过程中,直接写出点
到四边形
相邻两边距离相等时
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5138a9f70d5e8b0580e30fef6eb7baef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf1438142deeac876fc7dc50552e552.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://img.xkw.com/dksih/QBM/2021/9/9/2804599418290176/2810937245851648/STEM/de7d5c4efbc64905bda768af714b3339.png?resizew=249)
![](https://img.xkw.com/dksih/QBM/2021/9/9/2804599418290176/2810937245851648/STEM/9878e0fe89d14337a5de48714409b2cb.png?resizew=234)
![](https://img.xkw.com/dksih/QBM/2021/9/9/2804599418290176/2810937245851648/STEM/9878e0fe89d14337a5de48714409b2cb.png?resizew=234)
(1)求证:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1505d41fe799543518c642d87f6f6dc.png)
(2)请在图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/587458141d890533c0c32aa249a27ad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49437f474e5805688dff21ded2d1fd7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7788830ed1cb3b9c5988f70f43595f2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/399e8b3e7f6f461d9c75b9f73d3f252a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecf4b43b6792b9ae78a1c8cae4e60524.png)
①若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.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/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4256cf5ba235af7d42e41ac6e45195fe.png)
②在点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46085ca435d9e3582a8962fb0f60ba86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
解题方法
【推荐2】如图1,在△ABC中,BD、CE分别是边AC、AB上的中线,BD与CE相交于点O,M和N分别为OB、OC的中点,连接ED、EM、MN、ND.
![](https://img.xkw.com/dksih/QBM/2021/8/22/2791483608965120/2798084524802048/STEM/aca40a27af6349379c21c52a35f783fc.png?resizew=532)
(1)求
的值;
(2)当△ABC满足什么条件时,四边形DEMN是矩形?给出你的结论并证明.
(3)如图2,在△ABC中,BD、AF分别是边AC、BC上的中线,BD与AF相交于点O,若OA=4,OC=3,OB=5,则△ABC的面积为 (请直接写出结果).
![](https://img.xkw.com/dksih/QBM/2021/8/22/2791483608965120/2798084524802048/STEM/aca40a27af6349379c21c52a35f783fc.png?resizew=532)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f67b3a0878c7f08f7393cd06ccede0ea.png)
(2)当△ABC满足什么条件时,四边形DEMN是矩形?给出你的结论并证明.
(3)如图2,在△ABC中,BD、AF分别是边AC、BC上的中线,BD与AF相交于点O,若OA=4,OC=3,OB=5,则△ABC的面积为 (请直接写出结果).
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐3】已知点
是
任意一点,连接
并延长到点
,使得
,以
为邻边作平行四边形
,连接
,与
交于点
,连接
.
(1)如图1,若
为等边三角形,由三角形中位线定理可知,线段
与线段
的位置关系是______.数量关系为______.线段
与
的位置关系是______.数量关系为______
(2)拓展研究:如图2,若
为等腰直角三角形(
为斜边),(1)中的两个结论是否成立?若成立,请给予证明;若不成立,请写出正确的结论再给予证明.
(3)解决问题:如图3,若
是等腰三角形,
,请你直接写出线段
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/accad1bfa70bdcd7736bd9637fbd9ed8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f986188053acba1d28cd05311cb1289d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abe150bff3c4b46fc4032426a820ca9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cad4595d5352b2884568a59d8d766a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
(1)如图1,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/826c728050e3378921442ace20269ef6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)拓展研究:如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(3)解决问题:如图3,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bddefabbeb808377158c307bc0d903f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐1】已知抛物线
过点
,且与
轴交于点
.
(1)求该抛物线的顶点坐标;
(2)若有点A在直线
上,过点A作
轴于点B,以
为斜边,在
左侧作等腰直角三角形
.
① 当点Q与点A重合时,求点C到抛物线对称轴的距离;
② 若点C恰好落在抛物线上,求此时点C的坐标 .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3d2add1e8baa633327a28413678d1ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/405191e1f089bb41a2ed03fc576ee5b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2a8bd0328fe0741d3b619cf71c3a2c4.png)
(1)求该抛物线的顶点坐标;
(2)若有点A在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24624dffd30b66a5e4de57362b32b2a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
① 当点Q与点A重合时,求点C到抛物线对称轴的距离;
② 若点C恰好落在抛物线上,求此时点C的坐标 .
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
名校
【推荐2】在
中,
,D是
的中点,点F在边
上,过点D作
的垂线交直线
与点E.
,请说明理由;
【提出问题】如图②,当点E与点C不重合时,
还成立吗?
【解决问题】答:图②中的
依然成立;
下面是针对点E在线段
上的情形进行的一种证明,请你补充完整;
如图③,取
中点M,连结
.
,
,
点M是
的中点,
.(______________)(填依据)
,M是EF的中点,
,
.
点C、E、D、F在以_______为直径的圆上,
________.
由(1)可知,
,
.
【拓展应用】若
,当
的面积被
的一条边平分时,
的长为______.
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e779b4dbad5032b99a2df3b7dd46d3c.png)
【提出问题】如图②,当点E与点C不重合时,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e779b4dbad5032b99a2df3b7dd46d3c.png)
【解决问题】答:图②中的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e779b4dbad5032b99a2df3b7dd46d3c.png)
下面是针对点E在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
如图③,取
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/185f1a4ac6e77e9cf1f77acbbc31cfde.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54007b23d2c89135e36f038e30d181b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb1142eab9a23db919a7f69c5bf1a8fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16f3d198e76391779fa3badc848c8ac8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0215e13a9fb5574d5194aeb9507a98aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88f6784737ed8c7f0171ecb6afcf58d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5b883e9774dbe058b760adaea21f6e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ba04708acb775ed68a937bd8e0cd0b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50b6b0329c0461bca7c8d9878cb010c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fda7da8dda35c7dd610affba3fc0c25.png)
由(1)可知,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84d19311e1cb7f257049ac77b6a8bd90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56a80f9280f59b5560b134743d9ae10e.png)
【拓展应用】若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45fab13c011401eff8cdccf8c6fa1a36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐3】综合与探究
问题解决
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/b42d8962-5fe5-4abc-9852-7c68796e08f7.png?resizew=716)
如图1,
中,
,过点C作
于点D,小明把一个三角板的直角顶点放置在点D处,两条直角边分别交线段
于点 E ,交线段
于点 F,在三角板绕着点D旋转的过程中,若点E是
的中点,则点F也是
的中点吗?(注:可以用知识:直角三角形斜边上的中线等于斜边的一半)
“阳光”小组的解答是:若点E是
的中点,则点F也是
的中点.
理由如下:∵
于点 D,
.
∵点 E 是
的中点,
.
,
.
是等边三角形.
,
.
.
又
,
.
.即若点E是
的中点,则点F也是
的中点.
反思交流
(1)“群星”小组认为在这个题中,可以去掉条件“
”,其他条件不变(如图2),若点E是
的中点,则点F也是
的中点.请你根据条件证明这个结论;
拓广探索
(2)去掉条件“
”,其他条件不变旋转过程中,若
(如图3),那么等式
成立吗?请说明理由;
(3)去掉条件“
”,其他条件不变.若点 E 是
上任意一点(如图4),(2)中的结论还成立吗?请说明理由.
问题解决
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/b42d8962-5fe5-4abc-9852-7c68796e08f7.png?resizew=716)
如图1,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2fa001e22068705be6828b45f740fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0d801edd85c816522ae1e40b83ae9ba.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/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
“阳光”小组的解答是:若点E是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
理由如下:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4795ee1f96b430529934e2231b38885d.png)
∵点 E 是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f5a2ed6c268cc8fa7c1b415bcfcdf13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f021f27ea9e3bbe9384cb5cc74718617.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2604e21589dd55a97eefe5b6a18a535f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02135c5313031d8d8feaa42bc1b82bb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af0e4904c3e56d37433e2ac3180ea8f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25f8525f06540a4370ce2434ea7e29d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d60f1662ffed6383700d1f7c21a5e90.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d21b992de2fb72124680b3f3fe528f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bce9fd745dfcffdb32c76c2b47ed20d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a119013752d2e2e7b4f283d1fc8203.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
反思交流
(1)“群星”小组认为在这个题中,可以去掉条件“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3018c687427b6257767eda4a8c6612.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
拓广探索
(2)去掉条件“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3018c687427b6257767eda4a8c6612.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68fbbd17c89f03dbb61cd6ffdb9a0344.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e07ec735b9b33b68f6c1c5925e16b82.png)
(3)去掉条件“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3018c687427b6257767eda4a8c6612.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0d801edd85c816522ae1e40b83ae9ba.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
解题方法
【推荐1】如图,四边形
为菱形,
,点E在直线
上运动,
为等边三角形连接
.
![](https://img.xkw.com/dksih/QBM/2021/7/9/2760517787975680/2771795901071360/STEM/935a1816-3452-43be-949f-b983f3187de8.png)
(1)如图1,判断
的形状是__________﹔
(2)如图2,(1)中的结论是否成立?若成立请写出证明过程;若不成立,请说明理由!
(3)如果
,E为
四等分点,直接写出
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e918b70b02a73685e3c536c7f380e2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://img.xkw.com/dksih/QBM/2021/7/9/2760517787975680/2771795901071360/STEM/935a1816-3452-43be-949f-b983f3187de8.png)
(1)如图1,判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c105d6ba18fbb0581fb982175e2eac9.png)
(2)如图2,(1)中的结论是否成立?若成立请写出证明过程;若不成立,请说明理由!
(3)如果
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a91146605aff8a321203a5907143cd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c105d6ba18fbb0581fb982175e2eac9.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐2】在菱形ABCD中,
,E为对角线BD上一动点,连接AE.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/9/c1ddad00-b223-4240-91b3-5e9d793ee62c.png?resizew=587)
(1)如图1,点F为DE的中点,连接AF,若
,求
的度数;
(2)如图2,
是等边三角形,连接DM,H为DM的中点,连接AH,猜想线段AH与AE之间的数量关系,并证明.
(3)在(2)的条件下,N为AD的中点,连接AM,以AM为边作等边
,连接PN,若
,直接写出PN的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e075468e7fb0bf30229aec01a7205977.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/9/c1ddad00-b223-4240-91b3-5e9d793ee62c.png?resizew=587)
(1)如图1,点F为DE的中点,连接AF,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/062eeae4f31172ec99c10edc25697cad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d598f4a17ac14970ade9f381e9aee970.png)
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b05d6899d398fa4202a751d4c8981.png)
(3)在(2)的条件下,N为AD的中点,连接AM,以AM为边作等边
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c2b58424e893df4e01c912f87e09095.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d4746df85049d1651d3f6c30212a7a9.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐1】在等腰
中,
,直线
垂直平分
,交
于点
,点
在直线
上,且点
与点
关于点
对称,连接
.
是菱形;
(2)如图1,当
平分
时,求菱形
的周长;
(3)当四边形
为正方形时,请在图2中画出符合题意的正方形
,再连接
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa19c51dbbe45747c16bad72ebb48416.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3a51949f48ee8cf746851ba779b078e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.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/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09a4df7aed9496a5e4c1d29076470bb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/945e93c9f3515ded840de09a9ba81ce8.png)
(2)如图1,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/945e93c9f3515ded840de09a9ba81ce8.png)
(3)当四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/945e93c9f3515ded840de09a9ba81ce8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/945e93c9f3515ded840de09a9ba81ce8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐2】综合与实践
如图,在
中,
,
.
(1)如图1,若点
在
边上,
.将
沿
所在直线折叠,点
的对应点为点
.试猜想四边形
的形状并加以证明.
【数学思考】
(2)如图2,勤学小组受此问题启发,将
沿过点
的直线
折叠,点
的对应点为点
,且点
恰好落在
边上.若
,
,求
的长.
【问题解决】
(3)如图3,善思小组突发奇想,将
沿过点
的直线
折叠,若
,
,
,直接写出
的长.
如图,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eddf629bfb2d7b9daea6f2c1553360af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e3262fc038bbec5e7c8cc47df08bef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/093db5b63dfd1ac4c84692a168f7ace0.png)
(1)如图1,若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32ed407cbb778f76bf879bfcae69ebba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56bc4589f817e860a63c068bcf6aa88.png)
【数学思考】
(2)如图2,勤学小组受此问题启发,将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb5b12692517a39c320f99a479eb055.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65a3e478bb87d094e3a0af30dd10ae8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f0e65e147b109f2bbfd3a3f502bbc3a.png)
【问题解决】
(3)如图3,善思小组突发奇想,将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac8c89909407ddeb82ede5eb2ce6b01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4494a85de0be0b97a69348115aef8513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f45ffca1eb4ccf380f741d578f07724f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f0e65e147b109f2bbfd3a3f502bbc3a.png)
您最近一年使用:0次