What this calculator does
This calculator is designed for common triangle homework, geometry, construction, and measurement problems where you know some sides or angles and need the rest.
SASFind a missing side from two sides and the included angle.
SSSFind angles from three sides.
Formulac² = a² + b² − 2ab cos(C).
For classroom work, check the required rounding rules and whether angles are in degrees or radians. This page uses degrees.
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