How to Calculate Right Triangle
What is Right Triangle?
A right triangle has one 90° angle. The Pythagorean theorem (a² + b² = c²) relates its three sides: legs a and b, and hypotenuse c (opposite the right angle). Right triangles are fundamental in trigonometry, construction, and navigation.
Step-by-Step Guide
- 1Hypotenuse: c = √(a² + b²)
- 2Leg: a = √(c² − b²)
- 3Angles: angle A = arctan(a/b), angle B = arctan(b/a), sum of angles = 180°
- 4Area = (1/2) × base × height = (1/2) × a × b
Worked Examples
Input
Legs 3 and 4
Result
Hypotenuse = 5, angles 36.87° and 53.13°
Classic 3-4-5 right triangle
Input
Hypotenuse 10, one leg 6
Result
Other leg = 8
√(100−36) = √64 = 8
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