如图,在
中,D为斜边
的中点,E为
上一点,F为
中点,若
,
.
为
的角平分线;
(2)求
的长.
![](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/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e30e50e094cd2849e38859b36aad0b0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00ade06068471a9d76e32b417bef7551.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7316430d26a6f4bcc0bdadfd1a5330a.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
2024九年级下·全国·专题练习 查看更多[1]
(已下线)重难点04+平行四边形与特殊平行四边形(4考点8题型)1
更新时间:2024-06-16 14:33:16
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】在
中,以
为直径作
,
与
交于点
,连接
,点
为半圆
中点,连接
,
与
交于
,连接
,若
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/8/5eb1b209-31cb-4c15-967a-d1c9a25a20d4.png?resizew=139)
(1)求证:
为
切线;
(2)若
,求
的半径长.
![](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/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.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/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](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/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08cbd1d4bdcf1199ec44f9ba5348ac42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5d4af8d78b71920af9a3734d624bcc1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/8/5eb1b209-31cb-4c15-967a-d1c9a25a20d4.png?resizew=139)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f7c9f1677807c3334da4499444a6fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图,在
中,
,以
为直径作
,
,
分别交
于点
,
;求证:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/29/81817ebe-eb14-41ae-a785-960e98e96813.png?resizew=173)
(1)
;
(2)
是
的中点.
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.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/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/29/81817ebe-eb14-41ae-a785-960e98e96813.png?resizew=173)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d831c9ba6d18774540e2aaa29132fec9.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b19c646bcb6160197fdf12a9cb31a0d.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐3】定义1:如图1,若点H在直线l上,在l的同侧有两条以H为端点的线段MH、NH,满足
,则称MH和NH关于直线l满足“光学性质”;
定义2:如图2,在
中,
的三个顶点P、Q、R分别在BC、AC、AB上,若RP和QP关于BC满足“光学性质”,PQ和RQ关于AC满足“光学性质”,PR和QR关于AB满足“光学性质”,则称
为
的光线三角形.
阅读以上定义,并探究问题:
![](https://img.xkw.com/dksih/QBM/2022/1/7/2896488486494208/2901500262457344/STEM/90cbf4f3-6cf5-452d-882f-9e71568e33d8.png?resizew=604)
在
中,
,
,
三个顶点D、E、F分别在BC、AC、AB上.
(1)如图3,若FE
BC,DE和FE关于AC满足“光学性质”,求∠EDC的度数;
(2)如图4,在
中,作
于F,以AB为直径的圆分别交AC,BC于点E,D.
①证明:
为
的光线三角形;
②证明:
的光线三角形是唯一的.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e53497af8899cb299d762f1a4f46a55.png)
定义2:如图2,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c28abb154f41e1ca9816c9c9c2433ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c28abb154f41e1ca9816c9c9c2433ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
阅读以上定义,并探究问题:
![](https://img.xkw.com/dksih/QBM/2022/1/7/2896488486494208/2901500262457344/STEM/90cbf4f3-6cf5-452d-882f-9e71568e33d8.png?resizew=604)
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3018c687427b6257767eda4a8c6612.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
(1)如图3,若FE
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
(2)如图4,在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e68633cbbe3cc2d0801305f81a7aa86.png)
①证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
②证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
解答题-作图题
|
适中
(0.65)
【推荐1】如图,已知
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/3/43ca90ec-8c44-4241-9b9f-eb6d2b3706c5.png?resizew=146)
(1)求作线段
,使得点
在
边上,且
;(要求:尺规作图,不写作法,保留作图痕迹)
(2)在(1)的前提下,连接
,
相交于点
,若
,求
.
![](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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/3/43ca90ec-8c44-4241-9b9f-eb6d2b3706c5.png?resizew=146)
(1)求作线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c436f108fd4921dae15ecff19270237e.png)
(2)在(1)的前提下,连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28fb3269c8f548870addd9b8ad06ff14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd6a028c0e029371a72a1a2812f1c6ea.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】综合与实践
莹莹复习教材时,提前准备了一个等腰三角形纸片
,如图,
,
.为了找到重心,以便像教材上那样稳稳用笔尖顶起,她先把点B与点C重叠对折,得折痕
,展开后,她把点B与点A重叠对折,得折痕
,再展开后连接
,交折痕
于点O,则点O就是
的重心.
(1)初步观察:连接
,则
与
的数量关系是:________;
(2)初步探究:请帮助莹莹求出
的面积;
(3)猜想验证:莹莹通过测量惊奇地发现
,
.她的发现正确吗?请说明理由.
莹莹复习教材时,提前准备了一个等腰三角形纸片
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c8817091d0f4b7d7ac6df560cb63c68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07160f14b3b453bebb64cb2bf96dc85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.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/15c0dbe3c080c4c4636c64803e5c1f76.png)
如图,用铅笔可以支起一张均匀的三角形卡片.你知道怎样确定这个点的位置吗?![]() ![]() ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
(2)初步探究:请帮助莹莹求出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bbf9680f74a9ac5d934304654ce2771.png)
(3)猜想验证:莹莹通过测量惊奇地发现
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/321231b7c9c2902f953d47f0137bb823.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11995c96da35c9a923c86385e5a572ee.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,四边形
中,
平分
,E为
的中点,连接
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/11/3770aa61-650d-4798-9e9e-b8afc2a0e49a.png?resizew=157)
(1)求证:
;
(2)若
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/904442177786c6ffce3f61bdd4b0f22a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f27763f6dcbae61e12858d1893034164.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/11/3770aa61-650d-4798-9e9e-b8afc2a0e49a.png?resizew=157)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/098f2d934743e32a3668dd5e612716e3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50bf7f10d4adc9de8c22ead829e5c16d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ca07b4b1d1d30ebf0a5a402ad8aeecf.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,一架25米长的梯子
,斜靠在竖直的墙
上,梯子底端
到墙底端
的距离为7米.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/6/68b1cd55-1e9e-4197-bf48-468ece3e8794.png?resizew=122)
(1)若梯子的顶端
沿墙面下滑4米,那么底端
将向外移动多少米?请写出解题过程.
(2)在梯子
滑动过程中,
上是否存在点
,它到墙底端
的距离保持不变?若存在,请求出
的长;如果不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4cfef623a9534b5708df5f95f1760a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/6/68b1cd55-1e9e-4197-bf48-468ece3e8794.png?resizew=122)
(1)若梯子的顶端
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)在梯子
![](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/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
您最近一年使用:0次