# Pythagorean theorem

Save This Word!

noun Geometry.
the theorem that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides.
QUIZ
ARE YOU A TRUE BLUE CHAMPION OF THESE "BLUE" SYNONYMS?
We could talk until we're blue in the face about this quiz on words for the color "blue," but we think you should take the quiz and find out if you're a whiz at these colorful terms.
Question 1 of 8
Which of the following words describes “sky blue”?

## Origin ofPythagorean theorem

First recorded in 1905–10

## Words nearby Pythagorean theorem

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

## Scientific definitions for Pythagorean theorem

Pythagorean theorem
[ pĭ-thăg′ə-rēən ]

A theorem stating that the square of the length of the hypotenuse of a right triangle is equal to the sum of the squares of the lengths of the other sides. It is mathematically stated as c2 = a2 + b2, where c is the length of the hypotenuse and a and b the lengths of the other two sides.

## Cultural definitions for Pythagorean theorem

Pythagorean theorem
[ (puh-thag-uh-ree-uhn, peye-thag-uh-ree-uhn) ]

The theorem in geometry that, in a triangle with one right angle, usually called a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides.

## notes for Pythagorean theorem

The theorem is often expressed a2 + b2 = c2.

## notes for Pythagorean theorem

The simplest whole number expression of this theorem is called the 3, 4, 5 triangle. In a right triangle, if one side measures three units, and the second side measures four units, the hypotenuse must measure five units because 32 + 42 = 52; that is, 9 + 16 = 25.