A homeowner is converting a cleared plot of his land into a garden. The garden and the walkway around its perimeter have an area of 644 ft 2 .

A homeowner is converting a cleared plot of his land into a garden. The garden and the walkway around its perimeter have an area of 644 ft2. What is a quadratic equation that finds the width of the walkway if the garden is 20 ft. wide by 25 ft. long.