The perimeter of a rectangle is 370 m. If the length is 15 m less than three times the width, find the dimensions of the rectangle. What is the length?

Question

Can u please help me solve this ?

Answer 1

Hi Sam,

Denoted the width and length as W and L

L = 3W -15           (length is 3 times the width less 15 m: Always try to reword the problem)

P = 2L + 2W         (Standard formula for perimeter of a rectangle), P = 370 m

370 = 2L + 2W      (Subsitute the expression for L into this equation and solve for W)

370 = 2(3W -15) + 2W

370 = 6W - 30 + 2W

400 = 8W

400/8 = W 

W = 50 m,   L = 3W -15 = 3*50-15 =135

So the length of the rectangle is 135 m and the width is 50 m