已知：如图，在▱ABCD中，对角线AC，BD相交于点O．∠1=∠2．求证：▱ABCD是矩形．_刷题宝

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已知：如图，在▱ABCD中，对角线AC，BD相交于点O．∠1=∠2．求证：▱ABCD是矩形．

上一题下一题 0.0难度选择题更新时间:2019-11-04 03:14:24

答案(点此获取答案解析）

证明：∵四边形ABCD是平行四边形，

∴OA=OC，OB=OD，

∵∠1=∠2，

∴OA=OB，

∴OA=OB=OC=OD，

即AC=BD，

∴▱ABCD是矩形．

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