Question

A rectangle length is 8cm more than three times it’s widith. The perimeter is 128 cm find the length.

Answer 1

let x = width
length is 8 cm more than three times it’s width so length = 3x + 8

Perimeter of a rectangle = 2(L + W)
so
128 = 2(x + 3x + 8) solve for x (width)
128 = 2(4x + 8)
  64 = 4x + 8
  4x = 56
    x = 14
width = 14 cm
length = 3(14) + 8 = 50 cm

Answer:
width   = 14 cm
length  = 50 cm