如图,平行四边形ABCD的对角线交于点O,以OD,CD为邻边作平行四边形DOEC,OE交BC于点F,连接BE.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/17/f8f468f3-db0e-429a-974b-b8ef73845ac7.png?resizew=236)
(1)求证:F为BC中点.
(2)若OB⊥AC,OF=1,求平行四边形ABCD的周长.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/17/f8f468f3-db0e-429a-974b-b8ef73845ac7.png?resizew=236)
(1)求证:F为BC中点.
(2)若OB⊥AC,OF=1,求平行四边形ABCD的周长.
2020九年级·浙江宁波·学业考试 查看更多[6]
2020年浙江省宁波市南三县九年级学业诊断性考试数学试题2020年浙江省杭州下城区九年级二模联考数学试题2020年广西百色市右江区九年级毕业暨升学考试二模数学试题2021年河南省中考二模数学试题辽宁省阜新市第一中学2022-2023学年九年级上学期10月月考数学试题(已下线)第04讲 矩形的判定、判定与性质综合-【暑假自学课】2023年新九年级数学暑假精品课(北师大版)
更新时间:2022-10-14 18:28:26
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【推荐1】已知:如图1,四边形
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(2)如图2,连接
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【推荐2】如图,平行四边形
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(1)连接
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【推荐1】小颖、小亮想利用刚学过的测量知识来测量某公园的一棵古树
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【推荐2】如图1,在▱ABEF中,AB=2,AF<AB,现将线段EF在直线EF上移动,在移动过程中,设线段EF的对应线段为CD,连接AD、BC.
(1)在上述移动过程中,对于四边形的说法不正确的是B
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【推荐1】如图,矩形
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【推荐2】如图,在△ABC中,
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