Pythagoras Theorem — How to Calculate

    The Pythagorean theorem is one of the most famous formulas in mathematics, relating the three sides of a right-angled triangle.

    Pythagorean Theorem

    c² = a² + b²

    Where:

    • c = Hypotenuse (longest side)
    • a = One leg of the right triangle
    • b = Other leg of the right triangle

    Step-by-Step:

    1. 1

      Identify the sides

      Determine which sides you know and which you need to find.

    2. 2

      Square the known sides

      Calculate a² and b².

    3. 3

      Add or subtract

      For hypotenuse: c = √(a² + b²). For a leg: a = √(c² - b²).

    Worked Examples:

    Classic 3-4-5

    a: 3b: 4

    Result: c = 5

    c = √(9 + 16) = √25 = 5

    Distance

    a: 6b: 8

    Result: c = 10

    c = √(36 + 64) = √100 = 10

    Frequently Asked Questions