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如图,在菱形ABCD中,AB=2,∠B是锐角,AE⊥BC于点E,M是AB的中点,连结MD,ME.若∠EMD=90°,则cosB的值为 .
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如图在菱形ABCD中已知DE⊥ABAEAD=35BE=2则菱形ABCD的面积是______.
如图菱形ABCD中E.F.分别是AB.AC的中点若EF=3则菱形ABCD的周长是
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如图四边形ABCD的对角线ACBD互相垂直则下列条件能判定四边形ABCD为菱形的是
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如图在菱形ABCD中AB=5对角线AC=6.若过点A.作AE⊥BC垂足为E.则AE的长为.
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如图菱形ABCD的边长是2㎝E.是AB中点且DE⊥AB则菱形ABCD的面积为_________㎝2.
如图在平行四边形ABCD中E为BC边上的一点连接AEBD且AE=AB.1求证:∠ABE=∠EAD.2
如图菱形ABCD中AE⊥BC于点E.BE=CEAD=4cm.1求菱形ABCD的各角的度数2求AE的长
如图在菱形ABCD中E.是AB的中点且DE⊥ABAB=4.求1∠ABC的度数2菱形ABCD的面积.
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B
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D
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.如图在菱形ABCD中过点A.作AE⊥BC垂足E.为BC中点连接DEF.为DE上一点且∠AFE=∠B
如图菱形ABCD中AB=4∠B.=60°AE⊥BCAF⊥CD垂足分别为E.F连接EF则△AEF的面积
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如图在菱形ABCD中∠B.=60°AB=2E.F分别是BC.CD的中点连接AE.EFAF则△AEF的
如图在菱形ABCD中AC是对角线点E.F.分别是边BCAD的中点.1求证△ABE≌△CDF2若∠B.
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