Question 347410
Let's call the original side, x.
Thus the original area was x^2.
The new side is five more, or x+5.
And its area is {{{(x+5)^2 = x^2 + 10x + 25}}}.
The difference between them is 245, so we have
x^2 + 10x + 25 - x^2 = 245
Now solve...
10 x + 25 = 245
10x = 220
x = 22
x^2 = 484 ft^2