The definition of the Pythagorean Theorem is a mathmatical relationship of the lengths of the sides in a right triangle - if you square the length of the two shorter sides and add them together, that will equal the length of the longest side squared.(noun)
An example of the Pythagorean Theorem is a 3 x 4 x 5 triangle - 3 squared is 9, 4 squared is 16, and 5 squared is 25. 9 plus 16 equals 25.
See Pythagorean theorem in Webster's New World College Dictionary
See Pythagorean theorem in American Heritage Dictionary 4
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