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Triangle Calculator – Area, Perimeter & Angle Solver | Solvezi
Triangle Calculator – Area, Perimeter & Angle Solver | Solvezi
Calculate area, perimeter, and angles of any triangle.
This calculator uses the lengths of the three sides (Side-Side-Side or SSS) to determine all other properties of the triangle.
Calculated using Heron's Formula, which requires only the three side lengths (a, b, c).
s = (a + b + c) / 2 (Semi-perimeter)Area = √[s(s−a)(s−b)(s−c)]The total length of the boundary of the triangle.
P = a + b + cCalculated using the Law of Cosines.
The Law of Cosines is used to find an unknown angle when all three sides are known (SSS). We rearrange the standard formula c² = a² + b² − 2ab ⋅ cos(C) to solve for the angle C:
cos(C) = (a² + b² − c²) / (2ab)C = cos⁻¹ [ (a² + b² − c²) / (2ab) ]The calculator applies this formula three times (once for each angle A, B, and C) and then uses the inverse cosine (arccos or cos⁻¹) to get the final angle value in degrees or radians.
Triangles are classified by both their sides and their angles. The calculator determines the type based on the calculated side lengths and internal angles: