名校
1 . 小明在学习了圆内接四边形的性质“圆内接四边形的对角互补”后,想探究它的逆命题“对角互补的四边形的四个顶点在同一个圆上”是否成立.他先根据命题画出图形,并用符号表示已知,求证.
已知:如图,在四边形
中,
.
求证:点
在同一个圆上.
他的基本思路是依据“不在同一直线上的三个点确定一个圆”,先作出一个过三个顶点
的
,再证明第四个顶点
也在
上.
具体过程如下:
步骤一 作出过
三点的
.
如图1,分别作出线段
的垂直平分线
,
设它们的交点为
,以
为圆心,
的长为半径作
.
连接
,
(①______).(填推理依据)
.
点
在
上.
步骤二 用反证法证明点
也在
上.
假设点
不在
上,则点
在
内或
外.
ⅰ.如图2,假设点
在
内.
延长
交
于点
,连接
.
(②______).(填推理依据)
是
的外角,
(③______).(填推理依据)
.
.
这与已知条件
矛盾.
假设不成立.即点
不在
内.
ⅱ.如图3,假设点
在
外.
设
与
交于点
,连接
.
.
是
的外角,
.
.
.
这与已知条件
矛盾.
假设不成立.即点
不在
外.
综上所述,点
在
上.
点
在同一个圆上.
阅读上述材料,并解答问题:
(1)根据步骤一,补全图1(要求:尺规作图,保留作图痕迹);
(2)填推理依据:①______,②______,③______.
已知:如图,在四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd602a957d7f6d0940f79a1121b78c6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/16/c47d4791-3f7d-498a-ac80-1ac7ddf2393a.png?resizew=132)
求证:点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c82a10b4f0c9323d726804c89dd9548.png)
他的基本思路是依据“不在同一直线上的三个点确定一个圆”,先作出一个过三个顶点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
具体过程如下:
步骤一 作出过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
如图1,分别作出线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/374fe9986ebbc986fc422e514ab93a51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/16/93a582e4-1496-4432-9f4d-0da9602ef262.png?resizew=161)
设它们的交点为
![](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/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84c83984c62d390c6b30efa5d4e560de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf8109c7ef3b5f448187a18230381ff2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b1ffe501e7fd2693aee473b426fd4fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab609a6574633ebabcff3e73fa862081.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
步骤二 用反证法证明点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
假设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
ⅰ.如图2,假设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/16/4fbff140-e8a9-4d5f-8e33-8e6dccc33b37.png?resizew=143)
延长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6795cae2df43a722e1355e9562d93c09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d08df5c56bc4b5e8c36b0f42d53ec640.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/583061d83e4013cf3d4e51af1d6ad6d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ca4de204c6d5e4b7bfb00cfceb445e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5088b8cbc755b1d6b78e5185987b0796.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e98fccf0bb5849463bb3c7e69f30198.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/803c0a6e500e007441b642cbe3c9cda3.png)
这与已知条件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd602a957d7f6d0940f79a1121b78c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
ⅱ.如图3,假设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/16/08b8f3d0-9ffb-4bb4-bfa0-daa892697c5c.png?resizew=137)
设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c296e45b84cf67a98939aa7334e7d478.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4999f12484db6bb05f2b22ab76312e72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39b04e23ad5e1a1be625f73679c1a250.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b82e47950865fba90dbc5b31e21e928.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/953f36b59a6bec2e18de31c6da1b567c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a20e1a95fa95baa2911f30b88fb005d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/692bb8ba82ac5900b75a069d25c6fecb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/549aa6b3dc272af85c4a5fca6e4986b8.png)
这与已知条件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd602a957d7f6d0940f79a1121b78c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
综上所述,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c82a10b4f0c9323d726804c89dd9548.png)
阅读上述材料,并解答问题:
(1)根据步骤一,补全图1(要求:尺规作图,保留作图痕迹);
(2)填推理依据:①______,②______,③______.
您最近一年使用:0次
2024-01-13更新
|
205次组卷
|
2卷引用:北京市第十五中学2023-2024学年九年级下学期开学考试数学试题
2 . 下面是小橙设计的“已知两相交直线作矩形”的尺规作图过程:
(1)使用直尺和圆规,按照作法补全图(保留作图痕迹)
(2)完成下面的证明:
证明:
∵
,
,
∴四边形
是 .( )
∵
,
∴
,即
,
∴四边形
是矩形.( )(填推理的依据)
已知;如图,直线![]() ![]() ![]() 求作:矩形 ![]() 作法: ①在直线 ![]() ②以点O为圆心, ![]() ![]() ![]() ③连接 ![]() ![]() ![]() ![]() 即四边形 ![]() |
(1)使用直尺和圆规,按照作法补全图(保留作图痕迹)
(2)完成下面的证明:
证明:
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a23f35ebcd9799d82c1e41c09781a4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0866e1551b61074ca8e61261ecd1f9dc.png)
∴四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdad2e298d52079589e6de6d69d042e9.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ebe0cbafbb260627dc64d379a912247.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7de966c316db1013defc56372fcf814e.png)
∴四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
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3 . 下面是小茜设计的“作一个已知角的平分线”的尺规作图过程.已知:如图1,
.求作:射线
,使得
平分
.作法:如图2,
①在射线
上取一点C,以点O为圆心,
长为半径作弧交射线
于点D;
②分别以点C,D为圆心,
长为半径作弧,两弧交于点
(异于点O),连接
和
;
③作射线
.所以射线
平分
.
根据小茜设计的尺规作图过程.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/13/2419fd32-4c42-4a67-b084-baf20d34bb3c.png?resizew=278)
(1)使用直尺和圆规,补全图形(保留作图痕迹);
(2)完成下面的证明,并在括号内填写推理依据.
证明:∵
,
∴四边形
是 ( ),
∴
平分
( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7b2fe01a33c4825f9974ed9663a99c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7b2fe01a33c4825f9974ed9663a99c.png)
①在射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
②分别以点C,D为圆心,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
③作射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7b2fe01a33c4825f9974ed9663a99c.png)
根据小茜设计的尺规作图过程.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/13/2419fd32-4c42-4a67-b084-baf20d34bb3c.png?resizew=278)
(1)使用直尺和圆规,补全图形(保留作图痕迹);
(2)完成下面的证明,并在括号内填写推理依据.
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fbf2ad51ee93285aa3bf374852f1403.png)
∴四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/033274547930b2e2dcd4ea4919a36738.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7b2fe01a33c4825f9974ed9663a99c.png)
您最近一年使用:0次
名校
4 . 已知四边形是平行四边形,
.
(1)利用尺规作图作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2947ca8e0cdbeb4aab80ce9e7b63ba98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14833dbeed409b33acd4c9071fd0be36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
(2)求证:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
证明:∵四边形是平行四边形,
∴,
∴ ① ,
∵平分
,
∴
∴ ② ,
∴
又∵,
∴ ③ ,
又∵ ④ ,
∴四边形为平行四边形,
又∵ ⑤ ,
∴四边形是菱形.
您最近一年使用:0次
2023-07-03更新
|
255次组卷
|
3卷引用:重庆市第十一中学教育集团2023-2024学年九年级上学期开学考试数学试题
5 . 下面是小东设计的“过直线外一点作这条直线的平行线”的尺规作图过程.
已知:直线l及直线l外一点P.
求作:直线
,使得
.
作法:如图,
①在直线l上取一点A,作射线
,以点A为圆心,交
的延长线于点B;
②在直线l上取一点C(不与点A重合),作射线
,以点C为圆心,交
的延长线于点Q;
③作直线
.所以直线
就是所求作的直线.
根据小东设计的尺规作图过程,
(1)使用直尺和圆规,补全图形;(保留作图痕迹)
(2)完成下面的证明.
证明:∵
,
,
∴
( )(填推理的依据).
已知:直线l及直线l外一点P.
求作:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26d10d01d01eb7d3e619e59a48e04982.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/28/f36c09a6-4a92-4b34-b4c3-1da0d8d15813.png?resizew=387)
作法:如图,
①在直线l上取一点A,作射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
②在直线l上取一点C(不与点A重合),作射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
③作直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
根据小东设计的尺规作图过程,
(1)使用直尺和圆规,补全图形;(保留作图痕迹)
(2)完成下面的证明.
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9941b969048c0478a9d4116bfe4c6c32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d2960e9fd33f9487b81fb7f0ce5524.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26d10d01d01eb7d3e619e59a48e04982.png)
您最近一年使用:0次
6 . 下面是小明同学设计的“已知一组邻边构造平行四边形”的尺规作图过程.
已知:如图,线段
.求作:平行四边形
.
作法:①分别以A、C为圆心,
的长为半径画弧,两弧交于点D;
②连接
.四边形
即为所求作的平行四边形.
(1)请你使用直尺和圆规,帮助小明补全尺规作图过程(保留作图痕迹);
(2)证明上述作法所得的四边形
是平行四边形.
已知:如图,线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4515e1dff9a852b3294dc1d6488a5748.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
作法:①分别以A、C为圆心,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cdba2ac1a72eea482f5578843e00357.png)
②连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7e545f31f7cc57a31843f5adfd02941.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/23/dca98d12-8042-4cc6-8019-fd305d1f8e3f.png?resizew=151)
(1)请你使用直尺和圆规,帮助小明补全尺规作图过程(保留作图痕迹);
(2)证明上述作法所得的四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
您最近一年使用:0次
2023-08-12更新
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30次组卷
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2卷引用:广东省珠海市梅华中学2023-2024学年九年级上学期开学考试数学试题
7 . 学习完圆的切线后,数学兴趣小组经过探究得出“过一点作圆的切线”有两种情况“过圆上一点作圆的切线”和“过圆外一点作圆的切线”以下是两种情况作图作法.
根据小娟和小刚设计的尺规作图过程.
(1)使用直尺和圆规,补全其中一个图形(保留作图痕迹);
(2)填空:由作图可知“过圆上一点作圆的切线”可以作 条,“过圆外一点作圆的切线”可以作 条;证明所作的直线是圆的切线都用到了 (填依据).
过一个已知点作圆的切线 | |
小娟设计的“过圆上一点作圆的切线”的尺规作图过程. 已如:点A在 ![]() 求作: ![]() ![]() 作法:(1)作射线 ![]() (2)以点 ![]() ![]() (3)分别以点 ![]() ![]() (4)作直线AB,则直线 ![]() ![]() | 小刚设计的“过圆外一点作圆的切线”的尺规作图过程. 已知:如图, ![]() ![]() ![]() 求作:过点 ![]() ![]() 作法:(1)连接 ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() (2)以点 ![]() ![]() ![]() ![]() (3)作直线 ![]() ![]() ![]() |
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/28/f70658cb-d051-401d-aa53-305649a4c58a.png?resizew=291)
根据小娟和小刚设计的尺规作图过程.
(1)使用直尺和圆规,补全其中一个图形(保留作图痕迹);
(2)填空:由作图可知“过圆上一点作圆的切线”可以作 条,“过圆外一点作圆的切线”可以作 条;证明所作的直线是圆的切线都用到了 (填依据).
您最近一年使用:0次
名校
8 . 下面是小明设计的作菱形
的尺规作图过程.
已知:四边形
是平行四边形.
求作:菱形
(点
在
上,点
在
上).
作法:如图,
①以
为圆心,
长为半径作弧,交
于点
;
②以
为圆心,
长为半径作弧,交
于点
;
③连接
,所以四边形
为所求的菱形.
(2)完成下面的证明.
证明:
∵
,
,
∴______
______,
在平行四边形
中,
,
即
,
∴四边形
为平行四边形,(______)(填推理的依据)
∵
,
∴四边形
为菱形.(______)(填推理的依据)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
已知:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
求作:菱形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
作法:如图,
①以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.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/a0ed1ec316bc54c37c4286c208f55667.png)
②以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.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/2a30f3a8b673cc28bd90c50cf1a35281.png)
③连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
(2)完成下面的证明.
证明:
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14833dbeed409b33acd4c9071fd0be36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e92f48e9bfe12d145f7d2a2f0360d0.png)
∴______
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6706fe00b4e231e62d9ecbec567d526b.png)
在平行四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
即
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d61d846cbc5220533271c962b85c4b5.png)
∴四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14833dbeed409b33acd4c9071fd0be36.png)
∴四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
您最近一年使用:0次
2023-07-01更新
|
119次组卷
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12卷引用:北京师范大学附属实验中学2020-2021学年九年级上学期开学摸底测试数学试题
北京师范大学附属实验中学2020-2021学年九年级上学期开学摸底测试数学试题北京市丰台区2019- 2020学年八年级下学期期末练习数学试题北京市第四十三中学2020-2021学年八年级下学期期中数学试题北京市第二中学分校2021-2022学年八年级下学期期中数学试题北京市通州区运河中学2021-2022学年八年级下学期数学线上教学诊断试题福建省福州华侨中学2022-2023学年八年级下学期期中数学试卷福建省福州市长乐区2022-2023学年八年级下学期期中数学试卷北京市汇文中学2022-2023学年八年级下学期期中数学试题 北京市东城区东直门中学2022-2023学年八年级下学期期中数学试卷北京教育学院附属中学2022~2023学年八年级下学期期中数学试题北京市丰台第八中学2023-2024学年八年级下学期期中数学试题北京市海淀实验中学2023-2024学年八年级下学期期中数学试题
名校
9 . 如图,
中,
,
的平分线交
于点
.
![](https://img.xkw.com/dksih/QBM/2022/12/2/3122301076414464/3158575223717888/STEM/bc957fb965924b3d9fe87a82da87a817.png?resizew=209)
(1)尺规作图:作
的垂直平分线,分别交
、
、
于点
、
、
,连接
、
;(不写作法,保留作图痕迹)
(2)在(1)中所作的图形中,求证:
.补全下列证明过程:
证明:∵
垂直平分![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
∴
,
___________①___________
∵
平分![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
∴___________②___________
在
和
中,
,
∴
,∴___________④___________
∴
![](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/3818a2c9919d358b4c3713396093822b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://img.xkw.com/dksih/QBM/2022/12/2/3122301076414464/3158575223717888/STEM/bc957fb965924b3d9fe87a82da87a817.png?resizew=209)
(1)尺规作图:作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.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/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
(2)在(1)中所作的图形中,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0a3600b1760a63a10c9a0429b439dc1.png)
证明:∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2779662cf36bab7e33534c1ace192281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32217457c4e96e2ef155cf15c1b65d97.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
∴___________②___________
在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00870385ca7f3214e2971779eb4c7904.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7572ecc467c061ef71cf4486ec63ec3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef5eda4461c717f0c69037c3548631a7.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/936f4299ccd3ac4737416facc000b92c.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0a3600b1760a63a10c9a0429b439dc1.png)
您最近一年使用:0次
2023-01-23更新
|
237次组卷
|
2卷引用:重庆实验外国语学校2022-2023学年八年级下学期入学测试数学试题
10 . 下面是小李设计的“利用直角和线段作矩形”的尺规作图过程.
已知:如图1,线段
,
,及
.
求作:矩形
,使
,
.
作法:如图2,
①在射线
,
上分别截取
,
;
②以
为圆心,
长为半径作弧,再以
为圆心,
长为半径作弧,两弧在
内部交于点
;
③连接
,
.
∴四边形
就是所求作的矩形.
根据小李设计的尺规作图过程,解答下列问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/17/5196f35c-1e8a-4cdb-840e-5410e7a36cc3.png?resizew=390)
(1)使用直尺和圆规,依作法补全图2(保留作图痕迹);
(2)完成下面的证明.
证明:
,
,
四边形
是平行四边形( )(填推理的依据).
,
四边形
是矩形( )(填推理的依据).
已知:如图1,线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29d5edba610819321be4dd64e020386b.png)
求作:矩形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd64cfc4f355c60554b4f76c5ad17124.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/499812119541f60e7a606beb9d2418a4.png)
作法:如图2,
①在射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e4cb4069a2e1e90d1a9c4979ad09ca2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd64cfc4f355c60554b4f76c5ad17124.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/499812119541f60e7a606beb9d2418a4.png)
②以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abffb47edfada8d9c05750886aa662e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
③连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/764509115979e9958101808383672ec0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cdd9f345915ae742ed3dcd3f9678264.png)
∴四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
根据小李设计的尺规作图过程,解答下列问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/17/5196f35c-1e8a-4cdb-840e-5410e7a36cc3.png?resizew=390)
(1)使用直尺和圆规,依作法补全图2(保留作图痕迹);
(2)完成下面的证明.
证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8dd1554a0aa070f894de630ae87c1b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3e0f9e6f4c71cca3989b0cca571daf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ff8f71ba433771c40bdcc69d0011f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84263159b9b28291a5667da043ba7e48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2de0d10ef8b748d4531250c37c5d3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cb3f9a5da641be35117fd35ba07a6aa.png)
您最近一年使用:0次
2023-03-14更新
|
299次组卷
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5卷引用:北京市第四中学2023-2024学年九年级上学期开学考试数学试题
(已下线)北京市第四中学2023-2024学年九年级上学期开学考试数学试题北京市门头沟区2021-2022学年八年级下学期期末数学试题2023年新疆乌鲁木齐市中考数学一模试题北京市海淀区首师大附中2022-2023学年八年级下学期数学阶段性调研(3月)北京市燕山区2022—2023学年八年级下学期期中考试数学试卷