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One leg is 12 inches and the hypotenuse is 13 inches. How do you find the missing leg?

1 Answer
Mar 8, 2018


Recall that the sum of the squares of the legs is equal to the square of the hypotenuse in a right triangle


Thus, the square of 13 is equal to the square of 12 plus the square of the missing leg.

We can set up an equation with x as the unknown length.




#x=+-5# Disregard the #-5# because a side cannot have a negative length

Thus, the missing side is 5 inches.