Answer:
length = 20 cm
width = 9 cm
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