如图1,△ABC≌△DAE,∠BAC=∠ADE=90°。
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/25/1275c6ca-1481-41aa-94d5-694c4b40faee.png?resizew=484)
(1)连接CE,若AB=1,点B、C、E在同一条直线上,求AC的长;
(2)将△ADE绕点A逆时针旋转α(0°<α<90°),如图2,BC与AD交于点F,BC的延长线与AE交于点N,过点D,作
交BC于点M,求证:①BM=DM;②MN2=NF·NB.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/25/1275c6ca-1481-41aa-94d5-694c4b40faee.png?resizew=484)
(1)连接CE,若AB=1,点B、C、E在同一条直线上,求AC的长;
(2)将△ADE绕点A逆时针旋转α(0°<α<90°),如图2,BC与AD交于点F,BC的延长线与AE交于点N,过点D,作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf2638b8f4aefda11f23e3515448ace.png)
21-22九年级上·安徽合肥·期末 查看更多[4]
安徽省合肥市包河区2021-2022学年九年级上学期期末数学试题安徽省蚌埠市怀远实验教育集团2022-2023学年九年级上学期期中教学质量评估数学试卷 (已下线)2022年安徽省蚌埠中考二模数学试卷变式题21-23(已下线)安徽省合肥市2023-2024学年九年级上学期期末数学试题
更新时间:2022-07-20 15:05:44
|
相似题推荐
解答题-证明题
|
较难
(0.4)
【推荐1】如图1,已知直线
,点C为
,
内部的一个动点,连接
,
,
的平分线交直线
于点E,
的平分线交直线
于点A,
和
交于点F.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/7/b8b1a783-3bf3-4ed7-bd24-e696b5b65362.png?resizew=532)
(1)
,猜想
和
的位置关系,并证明;
(2)如图2,在(1)的基础上连接
,则在点C的运动过程中,当满足
且
时,求
的度数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfaad5f25944b5422c6c7e12071d6417.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7d19f963f7c803bcfcbb265ec6d4304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dea2ae9d515f9ab351ad72306b776ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d822262ff00915910e5b87d81ad1ba.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/4/7/b8b1a783-3bf3-4ed7-bd24-e696b5b65362.png?resizew=532)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4108da5935c53a3dc3f328d6e97598.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)如图2,在(1)的基础上连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b00a5239269d72d6f9632e7d77347106.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8bdd99f6772930b8dcdfcf07546efe7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/727ad3e630a224303d6d3b8ad5c114ba.png)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐2】已知:在
中,
.过
边上的点D作
,垂足为点E.
为
的一条角平分线,
为
的平分线.
,点G在边
上且不与点B重合.
①判断
与
的数量关系,并说明理由;
②判断
与
的位置关系,并说明理由;
(2)如图2,若
,点G在边BC上,DG与FB的延长线交于点H,用含
的代数式表示∠H,并说明理由;
(3)如图3,若
,点G在边
上,
与
交于点M,用含
的代数式表示
,则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb2cf0e95fdf1fd8a5b01d3dfd905e08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bffd657e48b15b9b54a55817e2c26b22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23dc2d2dd56fcc67698c45a6e0e48f80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33ac762a2899a58faa0d3ab44f1281fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
①判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5b69d40b75d582c4b8ffa2369af1d41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d57899ad4774aed9ccc7bd23db72153.png)
②判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce8f887360a533f0a25b0b34fb11f0a1.png)
(2)如图2,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/708d48b595c17d4dccf9b4086d7e664e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
(3)如图3,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/708d48b595c17d4dccf9b4086d7e664e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed2884b46c0b3b258154b393777e966a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/474d8c089759922188afc889fe7d67cd.png)
您最近一年使用:0次
解答题-计算题
|
较难
(0.4)
名校
【推荐1】【操作发现】如图(1),在△OAB和△OCD中,OA=OB,OC=OD,∠AOB=∠COD=45°,连接AC,BD交于点M.
①AC与BD之间的数量关系为 ;
②∠AMB的度数为 ;
【类比探究】如图(2),在△OAB和△OCD中,∠AOB=∠COD=90°,∠OAB=∠OCD=30°,连接AC,交BD的延长线于点M.请计算
的值及∠AMB的度数;
【实际应用】如图(3),是一个由两个都含有30°角的大小不同的直角三角板ABC、DCE组成的图形,其中∠ACB=∠DCE=90°,∠A=∠D=30°且D、E、B在同一直线上,CE=1,BC=
,求点A、D之间的距离.
①AC与BD之间的数量关系为 ;
②∠AMB的度数为 ;
【类比探究】如图(2),在△OAB和△OCD中,∠AOB=∠COD=90°,∠OAB=∠OCD=30°,连接AC,交BD的延长线于点M.请计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11c0fed1bec279a67db01c918711d4f5.png)
【实际应用】如图(3),是一个由两个都含有30°角的大小不同的直角三角板ABC、DCE组成的图形,其中∠ACB=∠DCE=90°,∠A=∠D=30°且D、E、B在同一直线上,CE=1,BC=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ce0249a3ff99c083fa4421877549db1.png)
![](https://img.xkw.com/dksih/QBM/2019/6/18/2228099074236416/2230403872718848/STEM/909cf4d42f944e678264a42f551b43a4.png?resizew=420)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐2】如图:已知菱形
中,
,点
为边
上一动点,连接
交
外角角平分线于点
,连接
,
,
交
于
点.
(1)如图
,①设
的度数为
,直接写出
的取值范围______;
②当点
为
中点时,连接
,求证:
;
(2)如图
,过点
作
的平行线
,且使
,连接
,
①证明:
;
②当
,
时,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d2af0fe0e7b2716fe131cf85f42bdef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/727ad3e630a224303d6d3b8ad5c114ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcdae78f4d3b8d8213ac3ac9a9567eb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcdae78f4d3b8d8213ac3ac9a9567eb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/5/6866f6ce-e515-4e09-91c0-0f151fa60016.png?resizew=468)
(1)如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aca89fc7578af7fbeeb6aeba9186afab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
②当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7e4fa04825ac7d071968056322d88be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/049a825c2499a80c64fce1660480f05c.png)
(2)如图
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcdae78f4d3b8d8213ac3ac9a9567eb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5be2e15d3ce4363dbc0414a58799f875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
①证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cb96e0331eebe80ed1ff610faf531fe.png)
②当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bba8e0d0a84be821e404c93852543ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6b1c57496d989b9c0bed4ec2618bdb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐1】如图,已知:在
中,
,
,将一块足够大的直角三角尺
按如图放置,顶点Р在线段
上滑动(且不与A、B重合),三角尺的直角边
始终经过点C,并且与
的夹角
,斜边
交
于点D.
(1)当
______°,
,此时
______°
(2)点Р在滑动时,当
长为多少时,
与
全等,为什么?
(3)点Р在滑动时,
的形状可以是等腰三角形吗?若可以,直接写出夹角
的大小;若不可以,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08313da7b66283d2e0b3987f3e6761f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a1be17e0a3e51cde1f50f384198e71e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470196de340941f131522a23ee4d760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/148e063b8ccc49f6745b32b418eb9659.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c8ffe24cf9f327aeb241225ab15ab1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/3/d55d1b2d-9bc3-492a-a029-f00700ce7d36.png?resizew=172)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9251dff989f7d60db751b73033dee269.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b047cbd00a88af3c95331a548fa89715.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f271031a3b20308a992fccc4a486752b.png)
(2)点Р在滑动时,当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3da7bcea5a45eeae211f5851f12a7517.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4234cf4d8159f5df0333bcc269ffe099.png)
(3)点Р在滑动时,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/177678001b2ccde1db8f57fa5e017002.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
您最近一年使用:0次
【推荐2】如图,已知
,
是
的平分线,
是射线
上一点,
.动点
从点
出发,以
的速度沿
水平向左作匀速运动,与此同时,动点
从点
出发,也以
的速度沿
竖直向上作匀速运动.连接
,交
于点
.经过
、
、
三点作圆,交
于点
,连接
、
.设运动时间为
,其中
.
![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/469effcb-90e3-4fd2-b4d8-2ad62dfa8851.png?resizew=195)
(1)求证:
是等腰直角三角形;
(2)设
的长为
,发挥你的空间想象力,观察因动点
、
的运动而得到的图形变化的全貌,指出
关于
的函数图象大致为( )
A.
B.
C.
D. ![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/26d54ff6-c6d4-4a4d-91be-702f93b49448.png?resizew=124)
(3)在(2)的条件下,求出
与
的函数关系式,并求出
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a563c50a7f6d10fa46339d7107fc85e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be99fa94a1f3e4964fcc13a14fab9ba5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27935c1ef4df2d52ac697678a3c8f39d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf3369e0ea90e8d5cf4b6b3c45c0fd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce62bfefacedc6efc521bddf80ea8155.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5631e6ec24d3d67bf4592313b6b3f4f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2c3d2cba96f6f03520c0b3f6e4da03e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5631e6ec24d3d67bf4592313b6b3f4f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88e9f7d1272b7344346b58b660aa260a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be99fa94a1f3e4964fcc13a14fab9ba5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.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/be99fa94a1f3e4964fcc13a14fab9ba5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/350e954f629c1901a5cec03558319e46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/418cb34a5390475fa6d36394282d2142.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9a153fb242b6005f5726fbf7093ab49.png)
![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/469effcb-90e3-4fd2-b4d8-2ad62dfa8851.png?resizew=195)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba70863115b0947e98214a7b2512167d.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd519623279626373048c1ba838e764f.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/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
A.
![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/ba5f1ad9-5ea5-4908-837f-b646ba28ae5d.png?resizew=125)
![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/e430c425-9e55-4320-8a87-d7444f27dd48.png?resizew=124)
![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/3a798fac-bd80-4bcc-995f-32dc4be44b02.png?resizew=123)
![](https://img.xkw.com/dksih/QBM/2021/5/7/2715985927602176/2722908854812672/STEM/26d54ff6-c6d4-4a4d-91be-702f93b49448.png?resizew=124)
(3)在(2)的条件下,求出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
【推荐3】若△ABC和△ADE均为等腰三角形,且AB=AC=AD=AE,当∠ABC和∠ADE互余时,称△ABC与△ADE互为“底余等腰三角形”,△ABC的边BC上的高AH叫做△ADE的“余高”.
![](https://img.xkw.com/dksih/QBM/2022/1/11/2892256693977088/2892909604855808/STEM/2198d0b500754b14b4f4a428200fc74c.png?resizew=398)
(1)如图1,△ABC与△ADE互为“底余等腰三角形”.
①若连接BD,CE,判断△ABD与△ACE是否互为“底余等腰三角形”:_______ (填“是”或“否”) ;
②当∠BAC=90°时,若△ADE的“余高”AH=
,则DE=_______;
③当0°<∠BAC<180°时,判断DE与AH之间的数量关系,并证明;
(2)如图2,在四边形ABCD中,∠ABC=60°,DA⊥BA,DC⊥BC,且DA=DC.
①画出△OAB与△OCD,使它们互为“底余等腰三角形”;
②若△OCD的“余高”长为a,则点A到BC的距离为_______(用含a的式子表示).
![](https://img.xkw.com/dksih/QBM/2022/1/11/2892256693977088/2892909604855808/STEM/2198d0b500754b14b4f4a428200fc74c.png?resizew=398)
(1)如图1,△ABC与△ADE互为“底余等腰三角形”.
①若连接BD,CE,判断△ABD与△ACE是否互为“底余等腰三角形”:_______ (填“是”或“否”) ;
②当∠BAC=90°时,若△ADE的“余高”AH=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2967337e3fcb228dded64ab0c41a17e0.png)
③当0°<∠BAC<180°时,判断DE与AH之间的数量关系,并证明;
(2)如图2,在四边形ABCD中,∠ABC=60°,DA⊥BA,DC⊥BC,且DA=DC.
①画出△OAB与△OCD,使它们互为“底余等腰三角形”;
②若△OCD的“余高”长为a,则点A到BC的距离为_______(用含a的式子表示).
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
真题
名校
【推荐1】如图,在Rt△ABC中,M是斜边AB的中点,以CM为直径作圆O交AC于点N,延长MN至D,使ND=MN,连接AD、CD,CD交圆O于点E
(1)判断四边形AMCD的形状,并说明理由;
(2)求证:ND=NE;
(3)若DE=2,EC=3,求BC的长.
(1)判断四边形AMCD的形状,并说明理由;
(2)求证:ND=NE;
(3)若DE=2,EC=3,求BC的长.
![](https://img.xkw.com/dksih/QBM/2019/7/18/2249562554777600/2250008130478080/STEM/37c95ea8ba094b16a3cfb692bee2f81d.png?resizew=206)
您最近一年使用:0次
解答题-问答题
|
较难
(0.4)
【推荐2】如图1,点P在正方形ABCD的对角线AC上,正方形的边长是a,Rt△PEF的两条直角边PE、PF分别交BC、DC于点M、N.
(1)操作发现:如图2,固定点P,使△PEF绕点P旋转,当PM⊥BC时,四边形PMCN是正方形.填空:①当AP=2PC时,四边形PMCN的边长是_________;②当AP=nPC时(n是正实数),四边形PMCN的面积是__________.
(2)猜想论证
如图3,改变四边形ABCD的形状为矩形,AB=a,BC=b,点P在矩形ABCD的对角线AC上,Rt△PEF的两条直角边PE、PF分别交BC、DC于点M、N,固定点P,使△PEF绕点P旋转,则
=_______.
(3)拓展探究
如图4,当四边形ABCD满足条件:∠B+∠D=180°,∠EPF=∠BAD时,点P在AC上,PE、PF分别交BC,CD于M、N点,固定P点,使△PEF绕点P旋转,请探究
的值,并说明理由.
(1)操作发现:如图2,固定点P,使△PEF绕点P旋转,当PM⊥BC时,四边形PMCN是正方形.填空:①当AP=2PC时,四边形PMCN的边长是_________;②当AP=nPC时(n是正实数),四边形PMCN的面积是__________.
(2)猜想论证
如图3,改变四边形ABCD的形状为矩形,AB=a,BC=b,点P在矩形ABCD的对角线AC上,Rt△PEF的两条直角边PE、PF分别交BC、DC于点M、N,固定点P,使△PEF绕点P旋转,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc8d08ed44ae7ed558a9d7d4c21c2e3e.png)
(3)拓展探究
如图4,当四边形ABCD满足条件:∠B+∠D=180°,∠EPF=∠BAD时,点P在AC上,PE、PF分别交BC,CD于M、N点,固定P点,使△PEF绕点P旋转,请探究
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc8d08ed44ae7ed558a9d7d4c21c2e3e.png)
![](https://img.xkw.com/dksih/QBM/2016/9/21/1574239469846528/1574239476219904/STEM/2667c564e3a5471491d464ca01086cd6.png?resizew=323)
您最近一年使用:0次