A triangle has sides A, B, and C. The angle between sides A and B is 7π12 and the angle between sides B and C is π12. If side B has a length of 26, what is the area of the triangle?
1 Answer
Aug 5, 2017
Explanation:
calculate the area ( A ) of the triangle using
∙xA=12ABsinC
where C is the angle between sides A and B
we require to calculate the side A
the third angle in the triangle is
π−(7π12+π12)=π3
using the sine rule in triangle ABC
Asin(π12)=26sin(π3)
⇒A=26sin(π12)sin(π3)≈7.77
⇒area( A)=12×7.77×26×sin(7π12)
⇒areaA≈97.568 to 3 dec. places