The length of a rectangle is 6 cm more than four times the width. If the perimeter of the rectangle is 42 cm, what are its dimensions?

a. length = 18 cm; width = 3 cm
b. length = 18 cm; width = 9 cm
c. length = 6 cm; width = 9 cm
d. length = 3 cm; width = 18 cm

1 answer

w = width
4w + 6 = length

P = 2w + 2L
42 = 2w + 2(4w + 6)

Solve for w