△ Triangle Calculator

Triangle Calculations Using Heron's Formula

Given three sides a, b, c, the area can be found using Heron's formula: Area = √(s(s-a)(s-b)(s-c)) where s = (a+b+c)/2 is the semi-perimeter. Angles are found using the law of cosines: cos(A) = (b² + c² - a²) / (2bc).

Triangle Types

Triangles are classified by sides (equilateral, isosceles, scalene) and by angles (acute, right, obtuse). The sum of all angles in any triangle is always 180 degrees. The triangle inequality states that the sum of any two sides must exceed the third.