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32 votes
32 votes
Joe built a tree house 12 ft. up in a tree. He wants to

build a ladder that will lean up against the tree so that
his house is easily accessible. If the bottom of the
ladder is 9 ft. from the tree, how tall must the ladder
be to rest directly against the house?

User G T
by
3.0k points

1 Answer

12 votes
12 votes
To find this, we simply do the pythagorean theorem. A^2+B^2=C^2. We do this because when the ladder is up against the tree, it creates a right triangle. 9ft is the base and the height is 12ft. We need to find C^2 which is the hypotenuse.
12^2+9^2=C^2
144+81=C^2
225=C^2
15=C
The ladder must be 15 feet tall
User Acolchagoff
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3.2k points