Calculating your other leg is straightforward once you know the Pythagorean Leg formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the Pythagorean Leg Calculator.
What is Pythagorean Leg?
The Pythagorean Leg calculation tells you your other leg from a few simple inputs. The figure you are solving for here is the other leg.
The Pythagorean Leg formula
The core formula is:
Other leg = √(Hypotenuse ^ 2 - Known leg ^ 2)Here is what each input means:
- Hypotenuse — a number. Example: 5.
- Known leg — a number. Example: 3.
How to calculate it step by step
- Write down the hypotenuse (for example, 5).
- Write down the known leg (for example, 3).
- Apply the formula above to get your other leg.
- Double-check the result with the Pythagorean Leg Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Hypotenuse | 5 |
| Known leg | 3 |
| Other leg | 4.0000 |
With hypotenuse of 5 and known leg of 3, the other leg works out to 4.0000.
Example 2
With hypotenuse of 10 and known leg of 3, the other leg works out to 9.5394.
| Result | Value |
|---|---|
| Other leg | 9.5394 |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
Prefer not to do the maths by hand? — the Pythagorean Leg Calculator does it instantly, for free, with the formula and a worked example built in.
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