Which law should be used to find the third side of a triangle when given two sides and the included angle (SAS)?
Show answer
Law of Cosines
The Law of Cosines, c² = a² + b² - 2ab cos(C), is a generalization of the Pythagorean theorem that applies to all triangles, not just right triangles.
Also asked as:
- To solve for the missing side in a Side-Angle-Side (SAS) triangle, which trigonometric law is applied?