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Pythagorean Theorem Calculator — Free Online Calculator

Finds the missing side of a right triangle using the Pythagorean theorem.

What is it?

The Pythagorean theorem calculator finds the missing side of a right-angled triangle: the hypotenuse from two legs, or a leg from the hypotenuse and the other leg.

Formula

Hypotenuse: c = √(a² + b²) Leg: a = √(c² − b²) Area of right triangle = (a × b) / 2

Example

Legs a = 3 m, b = 4 m → c = √(9 + 16) = √25 = 5 m. Classic 3-4-5 Pythagorean triple.

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