Pythagorean Theorem Calculator
Pythagorean theorem calculator
Solve missing right-triangle sides or validate whether three sides satisfy the theorem.
InputsForm3 fieldsLive
Result
Hypotenuse = 5
Using c = sqrt(a^2 + b^2). Area = 6, perimeter = 12.
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Formula
c = sqrt(a^2 + b^2) Symbol legend
| Symbol | Meaning | Unit | Copy |
|---|---|---|---|
a | First leg length of right triangle | length | |
b | Second leg length of right triangle | length | |
c | Hypotenuse length | length |
- Square each leg length.
- Add the squared terms together.
- Take the square root to get hypotenuse c.
Example
Worked example: a = 3, b = 4
- 1 a^2 = 9
- 2 b^2 = 16
- 3 c = sqrt(9 + 16) = sqrt(25) = 5
The hypotenuse is 5.
How
- Enter leg a length.
- Enter leg b length.
- Read the hypotenuse result and copy if needed.
Avoid
- Applying the theorem to triangles that are not right triangles.
- Forgetting to square both legs before summing.
- Using negative or zero side lengths.
FAQ
Can this find a leg instead of hypotenuse?
This tool is configured for hypotenuse from two legs. For full right-triangle outputs use Right Triangle Calculator.
What if one leg is zero?
A valid right triangle requires positive side lengths, so zero is rejected.
Is the result always larger than each leg?
Yes, in a right triangle the hypotenuse is the longest side.
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