名校
1 . 如图,在
中,
与
交于点
,以点
为顶点的
的两边分别与边
,
交于点
,
,且
与
互补.
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575849445187584/2575932187787264/STEM/700fc07ed8604261b1e4ad1c1cfafaee.png?resizew=127)
(1)观察猜想
若四边形
是正方形,则线段
与
有何数量关系?请直接写出结论.
(2)延伸探究
若四边形
是菱形,那么(1)中的结论是否成立?若成立,请画出图形并给出证明;若不成立,请说明理由.
(3)拓展证明
若
,探索线段
与
的数量关系,并证明你的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5138a9f70d5e8b0580e30fef6eb7baef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.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/2b2557547eecdc826b8282058802d217.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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b2557547eecdc826b8282058802d217.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2947ca8e0cdbeb4aab80ce9e7b63ba98.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575849445187584/2575932187787264/STEM/700fc07ed8604261b1e4ad1c1cfafaee.png?resizew=127)
(1)观察猜想
若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a299d2b999568e80be8005565ba209a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cad4595d5352b2884568a59d8d766a4.png)
(2)延伸探究
若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(3)拓展证明
若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19c691ca9b28ab952badcc89418d07e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a299d2b999568e80be8005565ba209a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cad4595d5352b2884568a59d8d766a4.png)
您最近一年使用:0次
2020·江西南昌·模拟预测
解题方法
2 . 问题探究
(1)如图1,
和
均为等腰直角三角形,
,点B,D,E在同一直线上,连接
.
①请探究
与
之间的位置关系;
②若
,则线段
的长为_________.
拓展延伸
(2)如图2,
和
均为直角三角形,
,
,
,
,
.将
绕点C在平面内顺时针旋转,设旋转角
为
,作直线
,连接
.当点B,D,E在同一直线上时,画出图形,并求线段
的长.
(1)如图1,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2689f0ce5ab3467d8214794d8acb2bd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fc75953bf5dcfa4af308c34bf9952d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28a77aa6c27acfffcc601d9ca7e6d4c7.png)
①请探究
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc8d4476b89bfdf868064ac49e18c726.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/14/5c8d34ee-f5ea-4b69-b15a-fe8607551585.png?resizew=300)
拓展延伸
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2689f0ce5ab3467d8214794d8acb2bd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fc75953bf5dcfa4af308c34bf9952d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a7e3a943e5bf040d783c12d67e6a258.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e32513c66bca1e2d1706d50a6615df1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18120a244d3a1f9c1688bf53eb2ad775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/348fb71fbc47fd87e9ce011652ef4186.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a0acc93490a6a784eb62201d93dd93d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/727ad3e630a224303d6d3b8ad5c114ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8b97a81538ab92a18236b676ee94d94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
3 . 完成下列各题:(1)证明推断,如图,在正方形
中,点E,Q分别在边
,
上,
于点O,点G,F分别在边
,
上,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/ad25655f-5a50-4bec-a5ed-a474cf7104d3.png?resizew=180)
①求证:
.
②推断:
的值为__________.
(2)类比探究,如图,在矩形
中,
m为常数),将矩形
沿
折叠,使点A落在
边上的点E处,得到四边形
,
交
于点H.连接
交
于点O,试探究
与
之间的数量关系,并说明理由.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/c50daa3e-f944-4e13-a08c-a52f9afa9b02.png?resizew=179)
(3)拓展应用,在(2)的条件下,连接
,当
时,若
,
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.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/8681dc7b0483bb527802389b03129b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b120804d2ffb03299f3586cd1e1c00b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/ad25655f-5a50-4bec-a5ed-a474cf7104d3.png?resizew=180)
①求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4e6ecc67e184645d2cde587f8aa8f76.png)
②推断:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31aa3b10781b0d2e7f542a130b043f79.png)
(2)类比探究,如图,在矩形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ccb1d7a76f6b8354d106c4ea47baabf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19191ca20cae3123d7df1b3a2ec5a857.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f541f7ae7c39082d202efd28805c54e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/c50daa3e-f944-4e13-a08c-a52f9afa9b02.png?resizew=179)
(3)拓展应用,在(2)的条件下,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1d318d706ca4ec954246a292293b91a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2f30860874820bca1a0a62d28f2095.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/054130673f4856dd9b3729b5bfa86a29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
您最近一年使用:0次
4 . (1)【问题发现】
如图①,正方形
的两边分别在正方形
的边
和
上,连接
.
填空:①线段
与
的数量关系为______;
②直线
与
所夹锐角的度数为_______.
(2)【拓展探究】
如图②,将正方形
绕点
逆时针旋转,在旋转的过程中,(1)中的结论是否仍然成立,请利用图②进行说明.
(3)【解决问题】
如图③,在正方形
中,
,点M为直线
上异于B,C的一点,以
为边作正方形
,点N为正方形
的中心,连接
,若
,直接写出
的长.
如图①,正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8d0e8404f347a0eb4c76f4d25d9bdac.png)
![](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/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
填空:①线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
②直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
(2)【拓展探究】
如图②,将正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8d0e8404f347a0eb4c76f4d25d9bdac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(3)【解决问题】
如图③,在正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae33911e41aa2f7004cc01e336f96bf0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fc13fe21e64d9b45614ed43be847904.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a6f856872cd504d322ae27919ef2db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a6f856872cd504d322ae27919ef2db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167d31eb8432b5c0364316e5048c23dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8aa4f914a8d2bf3a2742659ee7e9a520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/167d31eb8432b5c0364316e5048c23dd.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575851124441088/2575944789516288/STEM/cb9d740ad81647f18f4fd1a781e95e30.png?resizew=391)
您最近一年使用:0次
5 . 如图1,在
中,
,点P在斜边
上,点D、E、F分别是线段
、
、
的中点,易知
是直角三角形.现把
以点P为中心,顺时针旋转
,其中
.连接
、
、
.
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575847809572864/2575942330753024/STEM/f7c35754-6199-433b-8b6b-fb14c69328c1.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575847809572864/2575942330753024/STEM/3380a141-a83e-49df-98bc-f61d0d0398b4.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575847809572864/2575942330753024/STEM/4b236a48-b9db-4d18-a8de-532aaa6e4377.png)
(1)操作发现
如图2,若点P是
的中点,连接
,可以发现
______
______;
(2)类比探究
如图3,
中,
于点P,请判断
与
的大小,结合图2说明理由;
(3)拓展提高
在(2)的条件下,如果
,且
,在
旋转的过程中,当以点C、D、F、P四点为顶点的四边形与以点B、E、F、P四点为顶点的四边形都是平行四边形时,直接写出线段
、
、
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f8f88798ec42a58dccd212586382b23.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/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/783d872617eed2bbd474035156b6caaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575847809572864/2575942330753024/STEM/f7c35754-6199-433b-8b6b-fb14c69328c1.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575847809572864/2575942330753024/STEM/3380a141-a83e-49df-98bc-f61d0d0398b4.png)
![](https://img.xkw.com/dksih/QBM/2020/10/21/2575847809572864/2575942330753024/STEM/4b236a48-b9db-4d18-a8de-532aaa6e4377.png)
(1)操作发现
如图2,若点P是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fb26d84907c923278ac4626a9d58947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83a1d2a9288f8f73a0137cbaf5203a2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69e107de32446a9bf31dabdd15881d98.png)
(2)类比探究
如图3,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f8f88798ec42a58dccd212586382b23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df2e118d8156830746055c1b2e759ab0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/241c12b0b187978621683f63f0a3b56c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/269126dce7e64dfc6e9b5ad28717c782.png)
(3)拓展提高
在(2)的条件下,如果
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aabecf66d94e4094f9cc46fd8ee050f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
您最近一年使用:0次
6 . 定义:如果一个三角形一条边上的高与这条边的比值是3:5,那么称这个三角形为“准黄金”三角形,这条边就叫做这个三角形的“金底”.
【概念感知】
(1)如图1,在
中,
,
,
,试判断
是否是“准黄金”三角形,请说明理由.
![](https://img.xkw.com/dksih/QBM/2020/5/18/2465591574716416/2466226873851904/STEM/812087410d494db0b783c0817406775c.png?resizew=312)
【问题探究】
(2)如图2,
是“准黄金”三角形,BC是“金底”,把
沿BC翻折得到
,连AB接AD交BC的延长线于点E,若点C恰好是
的重心,求
的值.
【拓展提升】
(3)如图3,
,且直线
与
之间的距离为3,“准黄金”
的“金底”BC在直线
上,点A在直线
上.
,若
是钝角,将
绕点
按顺时针方向旋转
得到
,线段
交
于点D.
①当
时,则
_________;
②如图4,当点B落在直线
上时,求
的值.
【概念感知】
(1)如图1,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd0763b031b7e6b6d87ce3554ac482d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ebb33adb2310a6e03918761e68204a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392b9e1a179a6676362679354a9e7e51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://img.xkw.com/dksih/QBM/2020/5/18/2465591574716416/2466226873851904/STEM/812087410d494db0b783c0817406775c.png?resizew=312)
【问题探究】
(2)如图2,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0005e1ef60f6ddc5f9a83e3de1ef3b2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2465ee1fec12351943f15055dfd6ec73.png)
【拓展提升】
(3)如图3,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1095c036b49c3327baaa2c3c7f746134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9801a8426c3c1c8b7db1b54d07f4315f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aeb1aa7bc4a01962fc1297f17fa9128f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b185184dc2dc3894a0313fd13f26a59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eb97aff0960e2640314888a38e7169c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
①当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6c96cb3ac8290e09c55d4eb336a8608.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1ec5d678ec42846e1d28301e3bfd4be.png)
②如图4,当点B落在直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61f9215613b7b05217ed77268c238391.png)
![](https://img.xkw.com/dksih/QBM/2020/5/18/2465591574716416/2466226873851904/STEM/8ca234de8a464e40a1d7e1b5cac6d02a.png?resizew=404)
您最近一年使用:0次
2020-05-19更新
|
790次组卷
|
3卷引用:江西省抚州市金溪县第一中学2019-2020学年九年级下学期统一测试(一)数学试题
解题方法
7 . 【探究证明】:(1)某班数学课题学习小组对矩形内两条互相垂直的线段与矩形两邻边的数量关系进行探究,提出下列问题,请你给出证明.
如图1,矩形ABCD中,EF⊥GH,EF分别交AB,CD于点E,F,GH分别交AD,BC于点G,H.求证:
;
【结论应用】:(2)如图2,在满足(1)的条件下,又AM⊥BN,点M,N分别在边BC,CD上,若
,则
的值为____________;
【联系拓展】:(3)如图3,四边形ABCD中,∠ABC=90°,AB=AD=8,BC=CD=4,AM⊥DN,点M,N分别在边BC,AB上,则
=____________.
如图1,矩形ABCD中,EF⊥GH,EF分别交AB,CD于点E,F,GH分别交AD,BC于点G,H.求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3db61c8766cffeff04615177a78a4e6e.png)
【结论应用】:(2)如图2,在满足(1)的条件下,又AM⊥BN,点M,N分别在边BC,CD上,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0740b1958c9feed785d21aa18d0338c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1d42e47b9110ef86d38b4dce6f7194f.png)
【联系拓展】:(3)如图3,四边形ABCD中,∠ABC=90°,AB=AD=8,BC=CD=4,AM⊥DN,点M,N分别在边BC,AB上,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f710f8f1fa0df203765d18692ded6a91.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/2/257888ac-8d73-4efb-9446-fb72a12fe787.png?resizew=457)
您最近一年使用:0次
2020-10-14更新
|
392次组卷
|
2卷引用:江苏省江阴市青阳片2020-2021学年九年级10月诊断性抽测数学试题
8 . (1)初步探究:如图(1),点
、
分别在正方形
边
、
上,
于点
,小芳看到该图后,发现
,这是因为
和
都是
的余角,就会由______判定得出______≌______.
(2)类比发现:小芳进一步思考,如果四边形
是矩形,如图,且
于点
,她发现
,请你替她完成证明.
(3)拓展延伸:如图(3),若四边形
是平行四边形,试探究:当
与
满足什么关系时,使得
成立?并证明你的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](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/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1f87b02b744534ae1ed700d21fcceb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1db2c0955e5a5be47faf855bca738a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1428d4a45e569bc6e39005ea3c9c8ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6fc8bfdbf2a7e4ab5ef262b20611785.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/836ea820cf3732508cdd332ceb9395ce.png)
(2)类比发现:小芳进一步思考,如果四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1f87b02b744534ae1ed700d21fcceb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2753a0194119801844add1fbbe7745b.png)
(3)拓展延伸:如图(3),若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febc9a89d0d1c97b88c0f4acd32b4e67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9bebe23a3e351436edec2f6b4312fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2753a0194119801844add1fbbe7745b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/31/899aa5a5-818e-432e-8fb0-a982e7f2f060.png?resizew=570)
您最近一年使用:0次
名校
解题方法
9 . 问题背景
在
中,
,
,
,点
、
分别是边
、
上的动点,设
,
两点之间的距离为
,
、
两点之间的距离为
.
初步思考
(1)如图1,过点
作
的垂线,垂足为
,连结
、
.当
时,
________;
深入探究
(2)如图2,若
于
,以
,
为邻边作平行四边形
,当
时,是否存在
,使得平行四边形
的顶点
恰好落在
的边上?若存在,请求出
的值,若不存在,请说明理由.
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624371663798272/2625872083304448/STEM/432ee606-e870-4e23-8e86-cdb55f29ccf6.png?resizew=372)
拓展延伸
(3)如图3,连接
、
交于点
,若
,且满足
,判断
是否为定值?若是,请求出
的值;若不是,请说明理由.
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c8807117d0d649419fdda04c531cdc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82b74e2b6dae540571fdd509c4e966b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b939af5ba06e279cce39396aaf0fae06.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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
初步思考
(1)如图1,过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab17635a999236e8d2e35017a208d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7c57b07f75e97d9f84718bd495ebcf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbb388a36bd5caaa51b7e3c898e3c906.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ec0618ae3a4fde6d6220010af229b9a.png)
深入探究
(2)如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32c38dfd14dde969702dff97ef2270f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab17635a999236e8d2e35017a208d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7c57b07f75e97d9f84718bd495ebcf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bf6ff8ab059df730af48806b32edfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39cc033406da2cdd342308972c6701f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bf6ff8ab059df730af48806b32edfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624371663798272/2625872083304448/STEM/432ee606-e870-4e23-8e86-cdb55f29ccf6.png?resizew=372)
拓展延伸
(3)如图3,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef667b04a6656e8fd171a8743a27bdd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f173a03f2b6749db9f44f43efc79a15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://img.xkw.com/dksih/QBM/2020/12/29/2624371663798272/2625872083304448/STEM/8338454a-a216-4cc8-801d-5b5f973fa445.png?resizew=214)
您最近一年使用:0次
名校
10 . 如图1,菱形ABCD与菱形GECF的顶点C重合,点G在对角线AC上,且∠BCD=∠ECF=60°,
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/91395941-41ae-4b78-9e76-45e5086f60d0.png)
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/e6c6e7c6-c139-42ad-a35f-c4c955f547be.png)
(1)问题发现
的值为_______;
(2)探究与证明:将菱形GECF绕点C按顺时针方向旋转α角(0°<α<60°),如图2所示,试探究线段AG与BE之间的数量关系,并说明理由;
(3)拓展与运用:菱形GECF在旋转过程中,当点A,G,F三点在一条直线上时,如图3所示连接CG并延长,交AD于点H,若CE=2,GH=
,则AH的长为_______.
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/91395941-41ae-4b78-9e76-45e5086f60d0.png)
![](https://img.xkw.com/dksih/QBM/2020/8/30/2539160282415104/2558316547874816/STEM/e6c6e7c6-c139-42ad-a35f-c4c955f547be.png)
(1)问题发现
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45ec2c1bca9d89d16df525a45408aa76.png)
(2)探究与证明:将菱形GECF绕点C按顺时针方向旋转α角(0°<α<60°),如图2所示,试探究线段AG与BE之间的数量关系,并说明理由;
(3)拓展与运用:菱形GECF在旋转过程中,当点A,G,F三点在一条直线上时,如图3所示连接CG并延长,交AD于点H,若CE=2,GH=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
您最近一年使用:0次
2020-09-26更新
|
337次组卷
|
8卷引用:【校级联考】河南省周口市鹿邑县2019届九年级中考第一次模拟数学试题