9514 1404 393
Answer:
13.5 in
Explanation:
Let s represent the length of a short side. Then a long side is (s+4). The perimeter is ...
P = 4s +4(s+4)
124 = 8s +16
15.5 = s +2 . . . . . . divide by 8
13.5 = s . . . . . . . . . subtract 2
The shorter sides are 13.5 inches long.