Answer:
90 inches
Explanation:
12" in a foot so in order to convert 3' to inches after Walt apply it by 12. once you have that just the formula to find the perimeter.
3 × 12 = 36
the perimeter formula is: 2L + 2W = P
36 × 2 = 72 9 × 2 = 18
72 + 18 = 90
your answer should be 90 inches.