如图,四边形
中,
,
,连接
.
![](https://img.xkw.com/dksih/QBM/2021/6/26/2751478865797120/2752673953497088/STEM/192d40b2-107d-4086-829c-08173b93600a.png)
(1)求证:
;
(2)尺规作图:过点
作
的垂线,垂足为
(不要求写作法,保留作图痕迹);
(3)在(2)的条件下,已知四边形
的面积为
,
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4fd85cff10e8f192cfe0b0a8b2f4996.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/2021/6/26/2751478865797120/2752673953497088/STEM/192d40b2-107d-4086-829c-08173b93600a.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5d5f49c0d6162ea6264c23fdff924cf.png)
(2)尺规作图:过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
(3)在(2)的条件下,已知四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f08273d339dc5ddbb89aa67bb8205e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
2021·广西·中考真题 查看更多[3]
更新时间:2021-06-28 12:32:24
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,已知
ABC中,AB=AC=10cm,BC=8cm.点D为AB的中点,点P在线段BC上以3cm/s的速度由B点向C点运动,同时,点Q在线段CA上由C点向A点运动,并且点Q的运动速度与点P的运动速度不相等,设点Q的运动时间是t(s).
![](https://img.xkw.com/dksih/QBM/2021/11/3/2843092863451136/2899374903353344/STEM/c2b78833-dc8a-415c-b1ec-d7a0ee43332d.png?resizew=123)
(1)用含有t的式子表示:PC= cm;
(2)若
BPD与
CQP全等,求点Q的运动速度;
(3)若点Q以(2)中的运动速度从点C出发,点P以原来的运动速度从点B同时出发,都逆时针沿
ABC三边运动,求经过多长时间点P与点Q第一次在
ABC的哪条边上相遇?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://img.xkw.com/dksih/QBM/2021/11/3/2843092863451136/2899374903353344/STEM/c2b78833-dc8a-415c-b1ec-d7a0ee43332d.png?resizew=123)
(1)用含有t的式子表示:PC= cm;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
(3)若点Q以(2)中的运动速度从点C出发,点P以原来的运动速度从点B同时出发,都逆时针沿
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.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】已知:如图,点D为BC的中点,
,求证:
是等腰三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ba77f66ecad8eb4a7a63f169f28a3b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/18/66049119-4519-4406-a35f-d631eca6e6b9.png?resizew=131)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,
中,
,
.
![](https://img.xkw.com/dksih/QBM/2020/11/17/2600468671152128/2610494143692800/STEM/d9d3ff9b67ec4ec492ba48c12fb02aca.png?resizew=134)
(1)求作
的垂直平分线.(不写作法,保留痕迹);
(2)设l与
边交于点D,连接
,若
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d3c9ce32b721995f355eea411340e3.png)
![](https://img.xkw.com/dksih/QBM/2020/11/17/2600468671152128/2610494143692800/STEM/d9d3ff9b67ec4ec492ba48c12fb02aca.png?resizew=134)
(1)求作
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(2)设l与
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07160f14b3b453bebb64cb2bf96dc85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】用尺规“三等分任意角”是数学史上一个著名难题,它已经被数学家伽罗瓦用《近世代数》和《群论》证明是不可能的.但对于特定度数的已知角,如
角,
角等,是可以用尺规进行三等分的.下面是小明的探究过程:
已知:如图1,
.
求作:射线
三等分
.
①在射线
上取任一点
;
②分别以
为圆心,
长为半径画弧,两弧在
上方交于点
,在
下方交于点
,连接
;
③作直线
交
于点
;
④以
为圆心,
长为半径作圆,交线段
于点
(点
不与点
重合);
⑤作射线
.
所以射线
即为所求射线.
(1)利用直尺和圆规,依作法补全图形(保留作图痕迹);
(2)完成下面的证明.
证明:
,
为等边三角形.
.
.
为
的直径,
___________
.
又
,
平分
( )(填推理的依据).
.
.
即射线
三等分
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79a97bb4dcfab4ec7539bc783d563c49.png)
已知:如图1,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ccc37b189fa2cbc269ca0b233dac37.png)
求作:射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/484a0acec9e113e8dd9e3b8dadca3298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7b2fe01a33c4825f9974ed9663a99c.png)
①在射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
②分别以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed62d4cb2496a57ea1de1d12300b71e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
③作直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
④以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/683c590673eece14fea3319c4fd5eb55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
⑤作射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a88d3d4b81a9a3f78e5e84db21ce549.png)
所以射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a88d3d4b81a9a3f78e5e84db21ce549.png)
(1)利用直尺和圆规,依作法补全图形(保留作图痕迹);
(2)完成下面的证明.
证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c019874ff82a27facc6e7123b797ffa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa5c45af7795831efd1030e55d734839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ca2d3f1188d9e61fae8ef5010a16cc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/749551375ae158309db5d4cc9feed364.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/649105167435b241fd7ce9e2d736f214.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c72c070f4f4d2b44927391b59a1e755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7602dbd73330ece1bf72328751263008.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83873a9d782f2588c5eedbfe73f9bc2f.png)
又
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebb54dc30d523fdf73865d579dea75d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c3c063cf9e2c080338f12a6a68e79b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c9ec9a0b3a5aba39f61ac1ec5084a61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c9b47b1f7f72485f002f19f01faca2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc7570df57a6ac2356314c2cef74e1d.png)
即射线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/484a0acec9e113e8dd9e3b8dadca3298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7b2fe01a33c4825f9974ed9663a99c.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,在平行四边形
中,对角线
与
相交于点
,点
,
分别在
和
的延长线上,且
,连接
,
.
;
(2)当
平分
时,四边形
是什么特殊的四边形?请说明理由.
![](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/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.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/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86d1125b47dec1c5e93143ee59ad862a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/607cfabc1d421835b6b64109ad18f571.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9766e5eb6796dafc5ffe212afdfc43c0.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】
与
是两块全等的含
的三角板,按如图①所示拼在一起,
与
重合.
![](https://img.xkw.com/dksih/QBM/2020/3/14/2419364104208384/2419433377898496/STEM/542aac29472147119811369bd487c272.png?resizew=308)
(1)求证:四边形
为平行四边形;
(2)取
中点
,将
绕点
顺时针方向旋转到如图
位置,直线
与
分别相交于
两点,猜想
长度的大小关系,并证明你的猜想;
![](https://img.xkw.com/dksih/QBM/2020/3/14/2419364104208384/2419433377898496/STEM/052521c9c258477496bcae912be50c9f.png?resizew=276)
(3)在(2)的条件下,当旋转角为多少度时,四边形
为菱形.并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f8f88798ec42a58dccd212586382b23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2613e6a3ddcf05f66ebad8274d1933fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2a0d0fe010a942d48791897504e31c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd1adfe4cc6566218f19970c2fd3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://img.xkw.com/dksih/QBM/2020/3/14/2419364104208384/2419433377898496/STEM/542aac29472147119811369bd487c272.png?resizew=308)
(1)求证:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcca8b9ba7a9fdd7d18ce9c1e86d2cd5.png)
(2)取
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab8becbac365a75366ec3848330a36c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54f3cbee923ebf5179770f7dbb53b38f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ce768434bd7816df75a6f46b696c4d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5b1b15a4605fce993cb13aefbf40360.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1649e3d387a9ea089b6e1f0e9f2a0a81.png)
![](https://img.xkw.com/dksih/QBM/2020/3/14/2419364104208384/2419433377898496/STEM/052521c9c258477496bcae912be50c9f.png?resizew=276)
(3)在(2)的条件下,当旋转角为多少度时,四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e76b28e5de04b3504326b5b007606883.png)
您最近一年使用:0次