justyourcalculatorPythagorean Theorem Calculator
Enter two sides of a right triangle to find the third.
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Pythagorean Theorem Calculator
Solve a² + b² = c² for any side
Leave the side you want empty.
Hypotenuse c
5
- a
- 3
- b
- 4
- c
- 5
- Angle α (opposite a)
- 36.86989765°
- Angle β (opposite b)
- 53.13010235°
- Area
- 6
- Perimeter
- 12
How it was calculated
- a² + b² = c²
- c = √(a² + b²) = √(3² + 4²) = √(9 + 16) = √25
- c = 5
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How the pythagorean theorem calculator works
In a right triangle, the square of the hypotenuse (the side opposite the right angle) equals the sum of the squares of the other two sides: a² + b² = c².
To find the hypotenuse, c = √(a² + b²). To find a leg, a = √(c² - b²). When the answer isn't a whole number, it's also shown as a simplified square root, such as 5√2, which is the exact form most classes ask for.
Whole-number solutions like 3-4-5, 5-12-13 and 8-15-17 are called Pythagorean triples.
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
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