The perimeter p of the rectangle with length l and width w is: p = 2l + 2w that is, two times its length and two times its width, lets solve for the width w and substitute known data: <span>p = 2l + 2w </span>2w = p - 2l w = (<span>p - 2l</span>)/2 w = (56 - (2*12))/2 w = (56 - 24)/2 w = 32/2 w = 16 therefore the width of the rectangle is 16 in