A triangle has sides A,B, and C. If the angle between sides A and B is (pi)/3π3, the angle between sides B and C is pi/4π4, and the length of B is 5, what is the area of the triangle?

1 Answer
Jun 3, 2018

Area A_t color(brown)(= 7.92At=7.92 sq units

Explanation:

Area of triangle A_t = (1/2) a b sin CAt=(12)absinC

Law of Sines a / sin A = b / sin B = c / sin CasinA=bsinB=csinC

hat A = pi/4, hat C = pi/3, hat B = (5pi)/12, b = 5ˆA=π4,ˆC=π3,ˆB=5π12,b=5

a = (5 * sin (pi/4)) / sin ((5pi)/12) = 3.66a=5sin(π4)sin(5π12)=3.66

A_t= (1/2) * 3.66 * 5 * sin (pi/3) color(brown)(= 7.92At=(12)3.665sin(π3)=7.92 sq units