To the nearest foot, it would be 23 feet. I found this using the Pythagorean Theorem of a (squared) + b (squared) = c (squared). If you have 24 as the hypotenuse, you have to square this and subtract 64 (8*8) from it. That will equal 512. So you have to find the square root of that which is 22.62, which will round to 23 feet.