How to work it?

Question

If two opposite sides of a square are increased by 13 meters and the other sides are decreased by 8 meters, the area of the rectangle that is formed is 72 square meters. Find the area of the original square.

Answer 1

(L+13)(W-8)=72

LW + 13W -8L =72 + 104

LW 13W-8L = 176

that equation has an infinite number of solutions.

If you limit solutions to integers, then

original sides include a square 11 by 11 meters, 59 by 9 and 5 by 12 meters