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

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