1/2*ab*sin C a=5 b=8 C=60

$$\\A=\dfrac{1}{2}*5*8*(\dfrac{1}{2}\sqrt{3})\\
A=10\sqrt{3}=17.32$$

So...it looks as though we're trying to find the area of a triangle....we have

A = (1/2)(5)(8)sin60 = 20sin60 = 20(√3/2) = 10√3 sq units

Thanks, heureka......I should have gotten rid of that square root and used an approximation, too!!! I usually try to avoid "roots" and "negatives," if possible........