Can someone help me with finding area? I know it is divided into three triangles.
I've divided the area into a rectangle and a right triangle. (see attachment)
1. According to Pythagorean theorem the right triangle has a hypotenuse of 15 and the legs (20 - 8) and 9.
2. Consequently the rectangle has the demensions $\displaystyle 8 \times 19$
3. The complete area is:
$\displaystyle a = 8 \cdot 19 + \dfrac12 \cdot 9 \cdot 12 = 206$