Pythagorean Theorem Calculator
a² + b² = c². Solve for hypotenuse or missing leg of a right triangle.
Result
c (hypotenuse)
5.000000
√(3² + 4²) = √25 = 5.0000
- a3.000000
- b4.000000
- c5.000000
- Area½ab6.000000
- Perimeter12.000000
Step-by-step
- Pythagorean: a² + b² = c².
- Solving for c: √(3² + 4²) = √25 = 5.0000.
- Right triangle area = ½ × a × b = 6.0000.
How to use this calculator
- Pick what to solve for.
- Enter the two known sides.
- Read the missing side, area, and perimeter.
About this calculator
The Pythagorean theorem: in a right triangle, a² + b² = c² where c is the hypotenuse (opposite the right angle). Enables solving for any unknown side given the other two. Common Pythagorean triples (integer solutions): 3-4-5, 5-12-13, 8-15-17, 7-24-25. Used everywhere: distance formula, screen diagonal, picture-hanging, surveying.
Frequently asked
Only right triangles (one 90° angle). For non-right, use the law of cosines: c² = a² + b² − 2ab cos C.
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