An open box is to be constructed from a square piece of sheet metal by removing a square of 5 feet from each side. It is to hold 720 cu feet. What should the dimension of the sheet metal be? Taking test if you can answer immediately. Thanks. Solution we have, Volume = V = 5( x - 10)^2 5 (x-10)^2 = 720 (x-10)^2 = 144 x- 10 = 12 x = 22 feet the dimension = 22ft x 22ft.