A triangle has sides A, B, and C. The angle between sides A and B is π2 and the angle between sides B and C is π12. If side B has a length of 9, what is the area of the triangle?

1 Answer
Aug 12, 2016

=10.85

Explanation:

Clearly this is a right-angled triangle where base=B=9 and angle between A and C =π(π2+π12)=π(7π12)=5π12
Therefore we can write
BA=tan(5π12)
or
9A=3.73
or
A=93.73
or
A=2.41 (Pl.note A is the height)
Area of the triangle =12×height×base=12×2.41×9=10.85