Question

Please help, ASAP thank you very much. Benton has an extension ladder than can only be used at a length of 10 feet, 15 feet, or 20 feet. He places the base of the ladder 9 feet from the wall and needs the top of the ladder to reach 12 feet. Which ladder length would Benton need to use to reach this height on the wall? A. 20 feet B. 10 feet C. 15 feet D. None of these ladder lengths would reach this height.

Answer 1

The answer is a because
12 times 2 plus 16 times 2 is 56.
144 + 256 = 400
400 = Xx2
X = 20 feet.