A ladder is resting against a wall. The ladder and the ground make an angle of 45° and the ladder is 7 ft from the wall. How long is the ladder?

Question

anonymous · Answer

Just move all values to one side and leave the other side to zero and there's your quadratic formula.

Let x be the distance from the wall to the bottom of the ladder
Let 2x+1 be the length of the ladder

15^2 + x^2 = (2x+1)^2
4x^2 + 4x + 1 = 15^2 + x^2 I just expanded and switched the sides
3x^2 + 4x - 224 = 0
x^2 + 4x - 672 = 0 <-- bridge method is not in the NYC curriculum but I don't know about yours
(x+28)(x-24) = 0
(3x+28)(3x-24) = 0
(3x+28)(x-8) = 0
x = 8

anonymous · Answer

8.76 FT?