Set Up an Equation and Solve the Problem

Multiple Choice

Set up an equation and solve the problem. The difference of the areas of two squares is 288 square inches. Each side of the larger square is 3 times the length of a side of the smaller square. Find the length of a side of the larger square.

A) 6 in.
B) 18 in.
C) 3 in.
D) 9 in.
E) none of these