Perimeter is 2 x length + 2 x width We can write that as... P=2L+2W We also know the length and perimeter so we substitute and solve like this 90=2 x 27 + 2W 90=54+2W 90-54=54-54+2W (property of subtraction equality) 36=2W Divide by 2 (property of division equality) W=18
