A parallelogram has sides A, B, C, and D. Sides A and B have a length of #5 # and sides C and D have a length of # 4 #. If the angle between sides A and C is #(5 pi)/8 #, what is the area of the parallelogram?

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Answer 1 · 2016-02-27T10:36:11

#4*5*sin((5pi)/8) ~~18.48#

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The area of a paralllogram is given by the formula #1/2*Base*Height#

We therefore need to calculate the height #h# of the paralleogram.
#sin((5pi)/8) = h/A#
#:.h = Asin((5pi)/8) = 5sin((5pi)/8)#

The base is #C# which is given as #4#

The area is #4*5sin((5pi)/8) ~~18.48#