math
posted by jw .
A ladder leans against a brick wall, The top of the ladder touches the wall 10 feet from the ground. The ladder is 15 feet long. How far does the bottom of the ladder sit from the wall? Round to the nearest tenth.

Use the Pythagorean Theorem >> a^2 + b^2 = c^2
You know one leg is 10 and the hyptenuse is 15. Solve for the length of the other leg. 
The Pathagorean Therim
a squared + b squared = c squared
It's a triangle.
a squared is the unknown
Distance from wall =a squared
b squared is how high up the ladder is from the ground = 10'
c squared is the hypotenuse of the triangle = 15' long ladder