SOLUTION: a 15 foot ladder is placed against the wall of a house such that the botton of the ladder is at a distance of 10 feet from the wall. at what height does the ladder touch the house?

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Question 4353: a 15 foot ladder is placed against the wall of a house such that the botton of the ladder is at a distance of 10 feet from the wall. at what height does the ladder touch the house?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Picture the right triangle formed by this 15 foot ladder against the wall. The length of the ladder (15 feet) is the hypotenuse, and the legs of the triangle are the 10 feet distance from the bottom of the ladder to the wall, and also the height of the ladder, which is the unknown.

According to the Theorem of Pythagoras,
a%5E2+%2B+b%5E2+=+c%5E2, where "c" is the hypotenuse, and the legs are "a" and "b".

10%5E2+%2B+x%5E2+=+15%5E2
100+%2B+x%5E2+=+225

Subtract 100 from each side:
x%5E2+=+125

Take the square root of each side:
x+=+sqrt+%28125%29+or+-sqrt%28125%29

A side of a triangle cannot be negative, so the answer is
x+=+sqrt+%28125%29 or simplify the radical
x+=+sqrt+%2825%29+%2A+sqrt+%285%29
x+=+5+%2A+sqrt+%285%29

R^2 at SCC