Answer
Use the formula $K=\frac{ab\cdot \sin{(C)}}{2}$ (where $K$ is the area of the triangle).
Work Step by Step
We know that $K=\frac{ab\cdot \sin{(C)}}{2}$, where $C$ is the included angle of $a$ and $b$ and $K$ is the area of the triangle.
Hence, to find the area of a triangle where the lengths of two sides and the included angle are given, I simply use the formula above.
