# If sides A and B of a triangle have lengths of 12 and 3 respectively, and the angle between them is (7pi)/8, then what is the area of the triangle?

Apr 30, 2017

This can be solved using the sine rule!

#### Explanation:

The sine rule is used to find the area of the triangle

$\text{area} = \frac{1}{2} \left(a\right) \left(b\right) \sin C$

Angle $C$ has to be expressed in degrees, by multiplying $\frac{7 \pi}{8}$ by ${180}^{\circ} / \pi$

In this case, you have

$\text{area} = \frac{1}{2} \left(12\right) \left(3\right) \left(\sin {157.5}^{\circ}\right)$