Answer:
23 inches
Step-by-step explanation:
If we add 5 inches to the shortest side, all sides will be the same length and the perimeter will be 69 inches. The longest sides have length that is 1/3 that, or ...
... (1/3)·(64 +5 in) = 23 in
_____
You can solve for x, but you obviously don't need to.
The perimeter is ...
... (4x -2) + 2(4x -2 +5) = 64
... 12x +4 = 64
... 12x = 60
... x = 5
... 4x -2 +5 = 4·5 +3 = 23 . . . . the length of the longest side in inches
