Answer:
a = 35 and b=11 if u add it's 46 if u subtract it's 24
Find the area as iff it was a rectangle, then subtract the area of the triangle in the top left corner.
Area of rectangle = 20 x 18 = 360
Area of triangle = 1/2 x 4 x 3 = 6
Area of pentagon = 360 - 6 = 354 cm^2
See picture:

1. Remove the parenthesis using the next rules:

2. Start to remove the parentheses from the center to the edges:

<h2>Then, the solution is 8</h2>