Pythagorean Theorem Calculator

How to calculate hypotenuse

For a right triangle, the square of the hypotenuse equals the sum of the squares of the two shorter sides. Sides of three and four give a hypotenuse of five.

Formula

√(a² + b²)

Worked example

Side A

3

Side B

4

Applying the formula to these values gives 5 .

What should I check?

This formula applies to a right-angled triangle. Use the same length unit for both sides.

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