Question 497478
l = x + 3
w = x
2(x) + 2(x + 3) = 24
4x + 6 = 24 
4x = 18 cm.
x = 4.5 cm. This is the width.
3 + 4.5 = 7.5 cm. This is the length.
2(4.5) + 2(7.5) = 24 cm.
This does check.
Cleomenius.