A triangle has sides A, B, and C. The angle between sides A and B is (5pi)/12 and the angle between sides B and C is pi/12. If side B has a length of 1, what is the area of the triangle?

1 Answer
Feb 15, 2018

Area of right Delta ABC = color(green)(0.125

Explanation:

Given hatA = pi/12, b = 1, hat C = (5pi)/13

Third angle hat B = pi - (5pu)/12 - pi / 12 = pi/2

Hence it’s a right triangle.

a / sin A = b / sin B = c / sin C

a / sin (pi/12) = 1 / sin (pi/2) = c / sin ((5pi)/12) = 1, since sin (pi/2) = 1

a = sin (pi/12) = 0.2588

c = sin ((5pi)/12) = 0.9659

Area of right Delta ABC = (1/2) a c = (1/2) * 0.2588 * 0.9659 = color(green)(0.125