an open rectangular box is to be formed by cutting identical squares, each of side 2 in, one from each corner of a rectangular piece of cardboard, and then turning up the ends. If the area of the piece of cardboard is 160 in² and the box is to have volume 144 in³, what should have been the dimensions of the cardboard used?

2 answers

If the cardboard is x by y, then

xy = 160
2(x-4)(y-4) = 144

Now just solve for x and y.
See answer