1 . 如图,点C,E在线段
上,
,
,
都是等边三角形,其边长分别是3,2,1,连接
,分别交
于点M,N,则
的长为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a0acc93490a6a784eb62201d93dd93d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80109f84d1dd3432514ffa836f51d37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77a7e4a6765ce78b05ee97764771e01f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94fa63920952b62bef3d9d57309d8e21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/31/f55c4685-f001-48e0-93f9-657a8ee5e3b0.png?resizew=222)
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2 . 如图,在边长为1个单位长度的小正方形组成的网格中,小正方形的顶点叫格点,格点A,B的连线与格点C,D的连线交于点E,若经过点B,D,E作圆,则图中阴影部分的面积为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/31/250eeb18-6fe4-403e-80c0-1c509bc42371.png?resizew=209)
A.![]() | B.![]() | C.![]() | D.![]() |
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3 . 综合与实践
数学活动:
数学活动课上,老师提出如下数学问题:已知四边形
与四边形
都为正方形,
为
的中点,连接
,
,如图1,当点
在
上时,求证:
.
独立思考
(1)请你证明老师提出的问题;
合作交流
(2)解决完上述问题后,“翱翔”小组的同学受此启发,把正方形
绕点
顺时针旋转,当点
落在对角线
上时(如图2),他们认为老师提出的结论仍然成立.请你予以证明;
问题解决
(3)解决完上述问题后,“善思”小组提出如下问题,把正方形
绕点
顺时针旋转(如图3),当点
在同一条直线上时,
与
交于点
.若
,请直接写出
的值.
数学活动:
数学活动课上,老师提出如下数学问题:已知四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc7ee0ef8945ba1b90e59aed7cab889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f541f7ae7c39082d202efd28805c54e.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/a776eac67bbc30e382f5f7916a40cd12.png)
独立思考
(1)请你证明老师提出的问题;
合作交流
(2)解决完上述问题后,“翱翔”小组的同学受此启发,把正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc7ee0ef8945ba1b90e59aed7cab889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
问题解决
(3)解决完上述问题后,“善思”小组提出如下问题,把正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc7ee0ef8945ba1b90e59aed7cab889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/927456b0989846a2f1573844bbaa2105.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.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/71a670fd15b5142f53ff55cdd2696dec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e0ae50d5993a332b5cddb022eaa6f1e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/31/db3f888f-bf8c-4a7f-b5e6-c34855dd1136.png?resizew=491)
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4 . 如图,为了估算河的宽度,我们可以在河对岸选定一个目标点A,在近岸取点
和点
,观察者在点
.适当调整,使得
与
都与河岸
垂直.此时
与
相交于点
,若测得
,
,请利用这些数据计算河的宽度.
![](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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f004ea2c953004fda33db94ccebb3a00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e8366871a42c490aa76d5fc3d05dbca.png)
您最近一年使用:0次
2023-07-19更新
|
91次组卷
|
3卷引用:山西省大同市2022-2023学年九年级上学期2月期末数学试题
山西省大同市2022-2023学年九年级上学期2月期末数学试题(已下线)专题03 相似三角形的应用综合(五大类型)(题型专练)-2023-2024学年九年级数学上册《知识解读·题型专练》(北师大版)27.2.2相似三角形的性质课后作业A层
5 . 如图,
,
相交于点
,则
的长为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73b3c032441543354c154ee67d744abb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c1da969b4b46927ffc36ce270c27f6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
A.![]() | B.4 | C.![]() | D.6 |
您最近一年使用:0次
2023-07-19更新
|
178次组卷
|
2卷引用:山西省大同市2022-2023学年九年级上学期2月期末数学试题
6 . (1)【问题发现】
如图①,正方形
、
,将正方形
绕点
旋转,直线
、
交于点
,请直接写出线段
与
的数量关系是 ,位置关系是 .
![](https://img.xkw.com/dksih/QBM/2023/7/17/3282714861207552/3284199249739776/STEM/1afee646d64a47f38ac2fb5932a8afcf.png?resizew=169)
(2)【拓展探究】
如图2,矩形
、
,
,
,
,将矩形
绕点
旋转,直线
、
交于点
,(1)中线段关系还成立吗?若成立,请写出理由;若不成立,请写出线段
、
的数量关系和位置关系,并说明理由
![](https://img.xkw.com/dksih/QBM/2023/7/17/3282714861207552/3284199249739776/STEM/e1ba57e8ec3e44408bedb18d2b5dc291.png?resizew=184)
(3)【解决问题】
若
,
,矩形
绕点
旋转过程中,请直接写出当点
与点
重合时,求线段
的长.
如图①,正方形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2257da1e2425f2ea9ac7440f52659ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2257da1e2425f2ea9ac7440f52659ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://img.xkw.com/dksih/QBM/2023/7/17/3282714861207552/3284199249739776/STEM/1afee646d64a47f38ac2fb5932a8afcf.png?resizew=169)
(2)【拓展探究】
如图2,矩形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2257da1e2425f2ea9ac7440f52659ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58052cd7d89b0d8556f5a082162dc324.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbd639b0046364a95f2e7a1b3404f916.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d5d71dbfa1c9d0381b4501566bf59f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2257da1e2425f2ea9ac7440f52659ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://img.xkw.com/dksih/QBM/2023/7/17/3282714861207552/3284199249739776/STEM/e1ba57e8ec3e44408bedb18d2b5dc291.png?resizew=184)
(3)【解决问题】
若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/825b4d8a30df3008671b9eae1af54a5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4f348c452def7842ce8227c63db7f23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2257da1e2425f2ea9ac7440f52659ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
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7 . 阅读下列材料,并完成相应任务
托勒密,古希腊天文学家、地理学家和光学家,而他在数学方面也有重大贡献,下面就是托勒密发现的一个定理,圆内接四边形的两组对边乘积之和等于两条对角线的乘积.
下面是该定理的证明过程(部分)
已知:如图①四边形
是
的内接四边形
证明:以C顶点,
为一边作
交
于点E,使得
又∵
∴
∴
∴
,
又
,
∴
∴
∴
,
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/637a6cfd289a896591ce73d96e88845f.png)
∴
∴ 即![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf58a9bdef36c419fa61eba5812a3a8.png)
任务:
(1)请将“托勒密”定理的证明过程补充完整;
(2)当圆内接四边形
是矩形时,托勒密定理就是我们非常熟知的一个定理: .
(3)如图②若
,试探究线段
之间的数量关系,并利用托勒密定理证明这个结论.
托勒密,古希腊天文学家、地理学家和光学家,而他在数学方面也有重大贡献,下面就是托勒密发现的一个定理,圆内接四边形的两组对边乘积之和等于两条对角线的乘积.
下面是该定理的证明过程(部分)
已知:如图①四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf58a9bdef36c419fa61eba5812a3a8.png)
证明:以C顶点,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db866ecc0c098bfc32ec8a43b65bdd58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1c04af96b222b46740ad7e7b348090f.png)
又∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82ea372fa1cafc56e21c2e8f66f7b1a8.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e706839cbc8ebf6e505f6f54c148eff3.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d89b7bc56d4767b14d2041e8a62cb20e.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b1f2596e9196ccdec8d50fff730d6d0.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e1de3f6f6d1e49ed0c4f6f1553ea92.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76c533f30a72ead2da96844acbd27d8b.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15a1f8d275052c7fcb675e32f86d44d8.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e980806fbeff7647a1a0b4c4ea519fcc.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/637a6cfd289a896591ce73d96e88845f.png)
∴
∴ 即
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf58a9bdef36c419fa61eba5812a3a8.png)
任务:
(1)请将“托勒密”定理的证明过程补充完整;
(2)当圆内接四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(3)如图②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f08fd6cfab081917a0ac14ecdf5e098.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0d3055b122bf4953a3d6cc92ab03d74.png)
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8 . 如图,在
和
,D、
分别是
、
上的一点,
.
时,求证
.
证明途径可用下面的框图表示,请填写其中的空格
时,判断
与
是否相似,并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8ee6e1d480ece7117e1f87ebf4bbeea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5b3bd5e6bc2a0a277d279bb01af9584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb0628cecbfc98d390e5447d52414e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7d330f54bb9d32b9cb9c5128f1ffd74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e177634bd10eef23738b6815796fec7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f47e1cfa53212cf89d3ae38c0d9db19b.png)
证明途径可用下面的框图表示,请填写其中的空格
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9c478708fac3820f1ff2cbc64f6b190.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8ee6e1d480ece7117e1f87ebf4bbeea.png)
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9 . 如图在四边形
中,
,若
,则
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c78e297915d9058d34dff8b45a181086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf16b9529102652f061bd162c8ec1db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/378159b1fd0a7c0dc102de5366245760.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/24/60ebc0a0-c447-46ea-9045-052eae4a6e55.png?resizew=198)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
10 . 如图,在
中,
于点D,
于点E,
与
相交于点F,
(1)求证:
.
(2)连接
,小明进行了深入探究,他发现
,得到老师和同学们的认同,他利用(1)中的结论,具体推理过程如下:
∵![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9619bb7107b1e96b3708c338d21fb5b1.png)
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10a86aa62cdfa88231647f032ef523d3.png)
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17cbbcf3355599753727696e50e59726.png)
又∵![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65adb645633e9346c40f8f1db40dabad.png)
∴![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfd7390343b35d276e90508a6125987d.png)
请你仿照小明的方法证明
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70734a8e672376bb0bd1522e229f86a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f913298f0fae9f55377a8deab9f099dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/31/9033de5e-167d-4156-9883-728d1fa99605.png?resizew=193)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9619bb7107b1e96b3708c338d21fb5b1.png)
(2)连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfd7390343b35d276e90508a6125987d.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9619bb7107b1e96b3708c338d21fb5b1.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10a86aa62cdfa88231647f032ef523d3.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17cbbcf3355599753727696e50e59726.png)
又∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65adb645633e9346c40f8f1db40dabad.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfd7390343b35d276e90508a6125987d.png)
请你仿照小明的方法证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd8ae72c4f392fa791e16b61518a73f9.png)
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