Math CentralQuandaries & Queries


Question from Cassandra, a student:

how do u find a and/or b using the pythagorean theorem of a right triangle?

Hi there,

The Pythagorean theorem states that in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the two other sides. If we label the sides of the triangle a, b and c, and assume c is the hypotenuse, the "formula" for the theorem is c2 = a2 + b2. If you want to find a or b, simply isolate that variable in the formula before substituting the numbers:

c2 - a2 = b2 or c2 - b2 = a2
So sqrt(c2 - a2) = b or sqrt(c2 - b2) = a

If you plug in the values for the hypotenuse and the known side, you can then find the unknown side.

Hope this helps,


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