Let W = width of poster Since the length is 7 inches longer than the width, the length is represented by W + 7. We know the perimeter is equal to twice the length + twice the width and that is 110 inches. Mathematically that looks like: 2(W + 7) + 2(W) = 110 Now let's solve for W:
First, find the area wholely, 20x8 = 160. Then find the triangle which is 7x 8 divided by 2 is 28 and you subtract the whole are by the triangle which is 160 - 28 is 132
