A rectangular room is 3 times as long as it is wide, and its perimeter is 56 meters Given l = length and w = width, The perimeter of a rectangle is 2l + 2w, we have: l = 3w 2l + 2w = 56 Substitute equation (1) into equation (2) for l: 2(3w) + 2w = 56 6w + 2w = 56 To solve this equation for w, we type it in our math engine and we get: w = 7 To solve for l, we substitute w = 7 into equation (1): l = 3(7) l = 21