The Pythagorean theorem is one of the most famous theorems of geometry. It is often attributed to Pythagoras of Samos (Greece), who lived in the sixth century b.c. The theorem states that in any right triangle, the square of the hypotenuse of the triangle (the side opposite the right angle) is equal to the sum of the squares of the other two sides, or c2 = a2 + b2.
This theorem was probably known long before the time of Pythagoras; it is thought to have been used by the ancient Egyptians and Babylonians. Nevertheless, Pythagoras (or some member of his school) is credited with the first proof of the theorem.
The converse of the Pythagorean theorem is also true. That is, if a triangle with sides a, b, and c has c2 = a2 + b2, we know that the triangle is a right triangle.
"Pythagorean Theorem." UXL Encyclopedia of Science. . Encyclopedia.com. (February 20, 2018). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/pythagorean-theorem
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Py·thag·o·re·an the·o·rem / pəˌ[unvoicedth]agəˈrēən; pī-/ a theorem attributed to Pythagoras 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." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (February 20, 2018). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/pythagorean-theorem
"Pythagorean theorem." The Oxford Pocket Dictionary of Current English. . Retrieved February 20, 2018 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/pythagorean-theorem