已知菱形的面积为24cm2，一条对角线长为6cm，则这个菱形的周长是______厘米．
如图所示：
∵菱形的面积等于对角线乘积的一半，AC=6cm，S菱形ABCD=24cm2，
∴BD=8cm，AO=3cm，BO=4cm，
在Rt△ABO中，AB2=AO2+BO2，
即有AB2=32+42，
解得：AB=5cm，
∴菱形的周长=4×5=20cm．
故答案为：20．
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| Mr. White was holding a party at home to celebrate his sixtieth birthday. To make him happy, one of his women friends 1 to sing a song for him. Now she was singing. One guest turned to a 2 by his side and criticized the singer. "What a 3 voice!" he said. "Do you know 4 she is?" "Yes," was the answer," She is my wife." "Oh, I beg your pardon," the man said. "Of course her voice isn't bad, 5 the song is very bad. I wondered who wrote that awful song?" "I did," was the answer. | ||||
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