Missing Right Triangle Leg
Rearranging Pythagoras finds the missing perpendicular leg when the longest side and one leg are known.
Missing Right Triangle Leg
Triangles · 2 inputs
How to use this calculator
- Enter hypotenuse in cm.
- Enter known leg in cm.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Start with a dimensioned sketch and label the units beside every measurement. Distinguish the outer edge from an internal opening, and distinguish a radius from a diameter. A geometric model is most useful when the shape actually matches the assumptions in the formula.
The hypotenuse must be strictly longer than the known leg.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.
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