Trying to find the height of the bases of a trapezoidal backyard

Question

Bob’s backyard is in the shape of a trapezoid with a height of 60 feet. The shorter base is 8 feet shorter than the longer base and the area of the backyard is 2160 square feet. Find the length of each base of the Trapezoidal yard.

Answer 1

b=shorter base

b+8=longer base

A=(1/2)(h)(b+[b+8])

2160=(1/2)(60)(b+b+8)

2160=30(2b+8)

divide both sides by 30

72=2b+8

2b=64

b=32  feet

b+8=40 feet