Pythagorean Theorem Calculator

a² + b² = c²

📐 Leg a

Tip: leave this empty if you want to solve for a.

📐 Leg b

Tip: leave this empty if you want to solve for b.

📏 Hypotenuse c

Tip: leave this empty if you want to solve for c.

🧮 Area

—

Area uses the formula A = ½ × a × b.

📏 Perimeter

—

Perimeter P = a + b + c.

⚡ Quick Summary

Enter any two sides (with units). The calculator finds the third side, area, and perimeter.

📚 References

Topic	Key formula / note	Source
Pythagorean theorem	a² + b² = c²	Wikipedia
Right triangle area	A = ½ab	Any standard geometry text

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