如图,在菱形中,,是锐角,于点,是的中点,连接,.若,则的值为___________. 答案:【答案】【解析】延长DM交CB的延长线于点H.首先证明△ADM≌△BHM,得出AD=HB=4,MD=MH,由线段垂直平分线的性质得出EH=ED,设BE=x,利用勾股定理构建方程求出x,即BE,结合AB得出cosB的值.解:延长DM交CB的延长线于点H.如图所示:∵四边形ABCD是菱形,∴AB=BC=AD=4,AD∥CH,∴∠ADM=∠H,∵M是AB的中点,∴AM=BM
单句改错
1. Julia have to study for the test. A B C D2. Can she come to here early? A B C D3. It takes ten minutes go home. A B C D4. I don't knows when they're leaving. A B C D5. I can't join you because I have much too homework to do. A B C D
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