GWD24-31

nicboy

    

31

    

Each side of a
certain parallelogram has length 6. if the area of the parallelogram is 18.
which of the following is the measure of one of its angles?

    

A. 30’   B. 45’  
C. 60’   D. 90’   E.120’

    

Answer  A

为什么不能是 60’ 呢，因为我先算出高为3(3^(1/2), 那么根据 1: 3^(1/2) : 2,应该对应60‘。 谢谢