the perimeter of a rectangle is 58cm. the length is 7cm less than three times the width. find the length and width. (translate to a system of equations and solve)

length = 20 cm

width = 9 cm

Step-by-step explanation:

perimeter = 58 cm

58cm = 2*L+2*w equation 1

L = 3w - 7 equation 2

where:

L = length

w=width

so we have:

58 = 2 (3w - 7) + 2w

58 = 6w - 14 + 2w

58 + 14 = 8w

72 = 8w

w = 72/8

w = 9 cm = width

we have:

L = 3 (9) - 7 = 20 cm = length