SOLUTION: How far from the base of the house do you need to place a 15-foot ladder so that it exactly reaches the top of a 12-foot tall wall?

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Question 858462: How far from the base of the house do you need to place a 15-foot ladder so that it exactly reaches the top of a 12-foot tall wall?
Answer by ben720(159) About Me  (Show Source):
You can put this solution on YOUR website!
Because the wall and the ground are at a 90° angle to each other, those two are the legs, and the latter is the hypotenuse. To find the ground, first, we must use the pythagorean theorem:
a%5E2%2Bb%5E2=c%5E2
Next, plug in known values:
a%5E2%2B12%5E2=15%5E2
Square:
a%5E2%2B144=225
Subtract 144 from both sides:
a%5E2=81
Square Root both sides
a=9
The wall is 9 ft from the ground.