Triangle Calculator
Understanding Triangles
Triangles have three sides and three angles that sum to 180°. The law of cosines calculates angles from sides. Heron's formula calculates area from sides.
Key Formulas
- Law of Cosines: c² = a² + b² - 2ab cos(C)
- Heron's Formula: Area = √(s(s-a)(s-b)(s-c))
💡 Tips
- Triangle inequality: sum of any two sides > third
- Angles sum to 180°
- Right triangles have 90° angle
- Area = ½ × base × height