While working on the roof of his house, john leans a 15 foot ladder against a second story window. if the distance on the ground between the base of the ladder and the house is nine feet, at what height does the ladder reach the second story window? in your final answer, include all necessary calculations.

Okay, this sounds like you need to use the pythagorean theorem to solve this problem. since the ladder is 15 feet long and it is leaning it forms the hypotenuse. now you have the 9. since we have already defined what the hypotenuse is the nine can be one of the legs. as you might know, we need two legs to form a right triangle and to find the hypotenuse.  or we can subtract the hypotenuse from the leg. here is the first step. multiply 15 by the second power (15x15) and 9 by the second power (9x9). the second step is to subtract the sums (15x15=225 and 9x9=81). finally, you put what you got from the subtraction and put that under a square root (144= 12). john needs to get the ladder to 12 feet to reach the second story window.