posted by Naomi on .
A ladder is two feet longer than the height of a certain wall. When the top of the ladder is placed against the top of the wall, the distance from the base of the ladder to the bottom of the wall is equal to the height of the wall. How high is the wall?
Let x = height of wall and use Pythagorean theorem.
x^2 + x^2 = (x+2)^2 = x^2 + 4x + 4
Move all terms to left hand side of equation.
x^2 - 4x - 4 = 0
Unfortunately, I don't see how to factor this.