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Pythagorean theorem calculator step by step

Calculate the hypotenuse or a leg of a right triangle applying the Pythagorean theorem (a² + b² = c²), step by step.

Practice exercises on teorema de Pitágoras

How how the Pythagorean theorem works

In a right-angled triangle, a2 + b2 = c2, where c is the hypotenuse (the longest side) and a, b are the legs.

Hypotenuse: c = √(a2 + b2). Leg: a = √(c2 − b2) (the hypotenuse must be longer than the known leg).

ExampleLegs 3 and 4: how long is the hypotenuse?

Step-by-step solution

  1. c² = a² + b² = 3² + 4² = 9 + 16 = 25.
  2. c = √25 = 5.
Result: the hypotenuse is 5.

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Frequently asked questions

How do you calculate the hypotenuse?

The hypotenuse is the square root of the sum of the squares of the legs: c = √(a² + b²).

How do you calculate a leg using Pythagoras?

Subtract the square of the known leg from the square of the hypotenuse and take the square root: leg = √(c² − b²). The hypotenuse must be the longest side.

Is the calculator free?

Yes, the the Pythagorean theorem calculator is free. And if you want to practice with hundreds of instantly corrected exercises, you have a 5-day trial with no card required on Refuerzo.ai.