A triangle has sides A, B, and C. The angle between sides A and B is (2pi)/3 and the angle between sides B and C is pi/12. If side B has a length of 2, what is the area of the triangle?

1 Answer
Jul 24, 2017

The area of the triangle is =0.63u^2

Explanation:

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The angles are

hatC=2/3pi

hatA=1/12pi

Therefore,

hatB=pi-(2/3pi+1/12pi)=pi-(8/12pi+1/12pi)=3/12pi=1/4pi

The side b=2

We apply the sine rule to the triangle DeltaABC

a/sin hatA=b/sin hatB

a/sin(1/12pi)=2/sin(1/4pi)

a=2sin(1/12pi)/sin(1/4pi)=0.73

The area of the triangle is

area=1/2ab sin hatC

=1/2*2*0.73*sin(2/3pi)

=0.63u^2