Area = Length x width
Assuming width = x, that makes length = x + 2
[tex]24 = (x)(x + 2) \\ {x}^{2} + 2x = 24 \\ {x}^{2} + 2x - 24 = 0 \\ (x + 6)(x - 4) = 0 \\ x = - 6 \: or \: x = 4[/tex]
Since width can't be a negative number, so it's 4 feet.
Answer : Length is 6 feet.
Hope this helps. - M