A triangle has sides A, B, and C. Sides A and B have lengths of 10 and 8, respectively. The angle between A and C is (13pi)/2413π24 and the angle between B and C is (pi)/24π24. What is the area of the triangle?

1 Answer
Jun 29, 2016

Area of DeltaABC=38.636 sq. unit.

Explanation:

Let us denote by /_(A,C) the angle btwn. sides A & C.

Then, by what is given, we find, /_ (A,C)+/_ (B,C)=(13pi)/24+pi/24=(14pi)/24=(7pi)/12.

Hence, /_ (A,B)=pi-(7pi)/12=(5pi)/12.

Now by Formula from Trigo.,
Area of DeltaABC=1/2*A*B*sin/_ (A,B)=1/2*10*8*sin((5pi)/12)=40*sin75^o=40(0.9659)=38.636 sq. unit.