Pythagorean theorem

noun

Geometry.

1. 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.

Pythagorean theorem

1. 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 c ² = a ² + b ², where c is the length of the hypotenuse and a and b the lengths of the other two sides.

Word History and Origins

Origin of Pythagorean theorem¹

First recorded in 1905–10

Example Sentences

We still use the Pythagorean theorem and euclidean principles.

From Slate

The Big John experience led to job training and apprenticeship with the International Brotherhood of Electrical Workers union, learning everything from the Pythagorean theorem to power line safety: “How a bird that sits on a power line doesn’t get hurt because he’s part of the circuit. But if you touch him it will kill you.”

From Los Angeles Times

“You and her have very different perceptions. You guys are both grown . . . I understand there’s nuances and things are situational. Like, you know, this isn't Pythagorean theorem going on, but this is like multi-dimensional calculus. You're in the X direction, she's in a Y direction and I’m the Z direction. Like, I’m not even adjacent. I’m just like on a different parallel. It’s all perception.”

From Salon

Two high school students have proved the Pythagorean theorem in a way that one early 20th-century mathematician thought was impossible: using trigonometry.

From Scientific American

If verified, Johnson and Jackson’s proof would contradict mathematician and educator Elisha Loomis, who stated in his 1927 book The Pythagorean Proposition that no trigonometric proof of the Pythagorean theorem could be correct.

From Scientific American