George is building a fence around a rectangular dog run. He is using his house as one side of the run. The area of the dog run will be 240 square feet. The length of the run is 30 feet, and the width is (30 minus x) feet. The diagram below shows his plan.

Recall the formulas for area and perimeter: A = lw and P = 2l + 2w.


A rectangle labeled Dog run has a length of 30 feet and width of (30 minus x) feet.