A 9-foot long ladder is placed against the side of a building such that the top of the ladder reaches a window that is 6 feet above the ground. To the nearest tenth of a foot, what is the distance from the bottom of the ladder to the building?

You'll want to draw a triangle; if you imagine the ladder leaning against the building, it forms a right triangle with height "a" being the distance from the ground to the window, and the hypotenuse "c" being the length of the ladder. We want to solve for base "b", the distance between the foot of the ladder and the building.

Recall the Pythagorean theorem:

a^2 + b^2 = c^2

We know that a = 6 and c = 9. Plug these values in, and solve for b.