Set up figure, side length x, and width x-7. Set equation up
[tex]228 = (x)(x - 7) \\ 228 = {x}^{2} - 7x \\ {x}^{2} - 7x - 228 = 0 \\ (x - 19)(x + 12) = 0 \\ x = - 12 \\ x = 19[/tex]
Since the value x, cannot be negative, x is equal to 19. Therefore the length is 19, width 12 (19-7)