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HomemathPythagorean Theorem

Pythagorean Theorem

Calculate the missing side of a right triangle using the Pythagorean theorem (a² + b² = c²).

How to Use the Pythagorean Theorem

  1. 1

    Enter known sides

    Input the lengths of two sides of the right triangle.

  2. 2

    Select which side to find

    Indicate whether the unknown side is a leg or the hypotenuse.

  3. 3

    View the result

    See the missing side length and area of the triangle.

💡 Tips & Tricks

  • The hypotenuse is always the longest side and is opposite the right angle.
  • Use this for distance calculations — the distance formula is derived from the Pythagorean theorem.
  • Remember common triples (3-4-5, 5-12-13) for quick mental math.

Frequently Asked Questions