A triangle has sides A, B, and C. Sides A and B have lengths of 7 and 10, respectively. The angle between A and C is (pi)/8 and the angle between B and C is (3pi)/8. What is the area of the triangle?

1 Answer
Jan 7, 2017

S=35

Explanation:

If A/_C = pi/8 and B/_C = (3pi)/8 then as the sum of the internal angles of a triangle always equals pi, we have:

A/_B = pi-pi/8-(3pi)/8 = pi-(4pi)/8 = pi-pi/2 = pi/2

Thus this is a right triangle where A and B are the legs, and C is the hypotenuse.

So the area of the triangle is:

S = (A*B)/2 = (7*10)/2 = 70/2 = 35