Question 15785
If the square has a side length of x then the area will be {{{x^2}}} and the perimeter will be 4x.

So {{{4x+5 = x^2}}}
{{{x^2-4x-5=0}}}
(x-5)(x+1)=0 so the side length could be 5 or -1.
Only a side length of 5 feet makes sense in the context of the problem.