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Pythagoras' theorem




Pythagoras' theorem
Pythagoras' theorem demonstrated in the case of the 3, 5, 5 triangle (one having sides in the ratio 3:4:5). It can be seen by inspection that in this case a2 + b2 = c2. Other right-angled triangles, the ratios of whose sides can be expressed using only small integers are 5, 12, 13 and 8, 15, 17 triangles. Right: The ancient method of laying out a right angle using a knotted rope was known and used long before the time of Pythagoras.
The square of the length of the hypotenuse of a right triangle is the sum of the squares of the lengths of the two sides. This is usually expressed as a2 + b2 = c2.


Related entry

   • Pythagorean triplet


Related category

   • GEOMETRY