在
中,
,
是
的中点,
是
的中点,过点A作
交
的延长线于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/12/fbdeb3a7-0850-4915-9a51-669681cae1dc.png?resizew=207)
(1)求证:
;
(2)判断四边形
的形状,并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.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/6095bae4840bfa80f2468f94b2002d7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/12/fbdeb3a7-0850-4915-9a51-669681cae1dc.png?resizew=207)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c664d49c072d75a6ae408c36f8906691.png)
(2)判断四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94a5a2949b3d520ed03d57126c7d4d8d.png)
更新时间:2022-12-14 21:47:01
|
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】生活中到处都存在着数学知识,只要同学们学会用数学的眼光观察生活,就会有许多意想不到的收获,如图三幅图都是由一副直角三角板拼凑得到的,其中图1的两块三角板是
和
,图2的两块三角板是
和
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/14/8d7aa69f-0bd6-43c9-9178-fc5edbf446a3.png?resizew=730)
(1)求图1中的
的度数.
(2)在图2中已知
,求
的度数.
(3)在图3中,三角板的两个直角顶点重合,且两条斜边平行,则
______.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d4ce3f962c91f0d3c7b998b5fbb37b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc3322a2ad9a95bdc9fc576a7a158d4d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/14/8d7aa69f-0bd6-43c9-9178-fc5edbf446a3.png?resizew=730)
图1 图2 图3
(1)求图1中的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
(2)在图2中已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/542b5bc10c7341c04c22244f3ec16e6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f90026b96116424a245b335b1adb886b.png)
(3)在图3中,三角板的两个直角顶点重合,且两条斜边平行,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/494ba20b1444f524cf636961e4688ae8.png)
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解答题-证明题
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【推荐2】已知:如图,
,
,
,
.求证:
.
,
( )
∴
(垂直的定义)
∴
( )
∴
( )
∵
( )
∴
(等量代换)
∴
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee662ef4fc90d0bbee6f1966722999d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab00e0cff0876c4183a47f1272cf9928.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e53497af8899cb299d762f1a4f46a55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/117878cbd8c00f2aabcdf62b487e2dc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee662ef4fc90d0bbee6f1966722999d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe6b3ca81687641f88d522f99fafbe6.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afedac49ce38f25e0a73e579133afe5a.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cc310194575262fb45352c2fbc19868.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e53497af8899cb299d762f1a4f46a55.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc7e519bf05b6eec5dfa0abcd5f2119c.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/117878cbd8c00f2aabcdf62b487e2dc7.png)
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解答题-证明题
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(0.65)
【推荐1】如图,在四边形
中,
,
,BD的垂直平分线交
、
分别于点E、F,连接
、
.
(1)求证:四边形
为菱形;
(2)若
,
,求四边形
的周长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e3262fc038bbec5e7c8cc47df08bef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/1/8177c2e4-4eb5-425e-8331-041ace87382d.png?resizew=155)
(1)求证:四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c87e1fe20bb0e8292e993657e14bc79a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07140f277a35733d8c97577ccdd4e3ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e673ef2d48215ca84a48377f17d6df00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c87e1fe20bb0e8292e993657e14bc79a.png)
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解答题-作图题
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适中
(0.65)
【推荐2】如图,在Rt△ABC中,∠ABC=90°,AB=BC,点E为线段AB上一动点(不与点A,B重合),连接CE,将∠ACE的两边CE,CA分别绕点C顺时针旋转90°,得到射线CE,,CA,,过点A作AB的垂线AD,分别交射线CE,,CA,于点F,G.
(1)依题意补全图形;
![](https://img.xkw.com/dksih/QBM/2019/2/18/2143237592129536/2143351589257216/STEM/b81e8b2bf90741669883d681928efa72.png?resizew=128)
(2)若∠ACE=α,求∠AFC 的大小(用含α的式子表示);
(3)用等式表示线段AE,AF与BC之间的数量关系,并证明.
(1)依题意补全图形;
![](https://img.xkw.com/dksih/QBM/2019/2/18/2143237592129536/2143351589257216/STEM/b81e8b2bf90741669883d681928efa72.png?resizew=128)
(2)若∠ACE=α,求∠AFC 的大小(用含α的式子表示);
(3)用等式表示线段AE,AF与BC之间的数量关系,并证明.
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
【推荐1】如图,菱形ABCD的对角线AC、BD相交于点O,过点D作DE⊥BC于点E,连接OE.若OA=8,S菱形ABCD=96,求DE和OE的长.
![](https://img.xkw.com/dksih/QBM/2021/7/29/2774437371150336/2780530027372544/STEM/42c2afe4cfee4e729537893347db5ce8.png?resizew=201)
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解答题-证明题
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适中
(0.65)
名校
【推荐2】如图,等腰Rt△ABC,AB=6,点E是斜边AB上的一点(端点A、B除外),将△CAE绕C逆时针旋转90°至△CBF,连接EF,且EF的中点为O,连OB、OC,设AE=x,
(1)求证:OB=OC;
(2)用x表示△BEF的面积S△BEF,并求S△BEF的最大值;
(3)用x表示四边形BECF的周长C,并求C的最小值.
(1)求证:OB=OC;
(2)用x表示△BEF的面积S△BEF,并求S△BEF的最大值;
(3)用x表示四边形BECF的周长C,并求C的最小值.
![](https://img.xkw.com/dksih/QBM/2020/2/17/2400798720892928/2401151410176000/STEM/72832220ac874090a65be17672f4456b.png?resizew=216)
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解答题-证明题
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适中
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【推荐1】如图,在四边形ABCF中,∠ACB=90°,点E是AB边的中点,点F恰是点E关于AC所在直线的对称点.
(1)证明:四边形CFAE为菱形;
(2)连接EF交AC于点O,若BC=10,求线段OF的长.
(1)证明:四边形CFAE为菱形;
(2)连接EF交AC于点O,若BC=10,求线段OF的长.
![](https://img.xkw.com/dksih/QBM/2019/3/2/2151657354174464/2152509096738816/STEM/7b2d278a7a1d4be199c03ccfc17b8813.png?resizew=107)
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解答题-证明题
|
适中
(0.65)
【推荐2】在
中,
平分
,
于点
,交
于点
,
,连接
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/17/fb7de5e4-ca2c-452c-9aae-a6fd6785e62d.png?resizew=293)
(1)求证:
;
(2)当
满足什么条件时四边形
是正方形?请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/854f480c60b88b546cb15d3b5622e212.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf04e3f561f74008429dece5d8a800c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52a6f7013c57cf7fb36bf3b73f3aa8b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/701f3b0e2bedfe5195443459072d798e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/252053b853152bd294a8315debd00b92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/17/fb7de5e4-ca2c-452c-9aae-a6fd6785e62d.png?resizew=293)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6ec32a384838d4051465ee81bdf9d7d.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/854f480c60b88b546cb15d3b5622e212.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1d70676406f26d339465fe3473c0c05.png)
您最近一年使用:0次