题目

已知:如图,AB=CD,DE⊥AC,BF⊥AC,E,F是垂足,DE=BF. 求证:(1)AF=CE; (2)AB∥CD. 答案:证明:(1)在Rt△ABF和Rt△CDE中,∵ ∴Rt△ABF≌Rt△CDE(HL). ∴AF=CE. (2)由(1)知∠ECD=∠FAB,即∠ACD=∠CAB, ∴AB∥CD.As a writer _____ the new century, he is popular among the teenagers.A.belongs B.belongs toC.belonging D.belonging to
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