1. Law of cosines relates the lengths of the sides of a triangle to the cosine of one of its angles.
2.you can write the Law of Cosines for each angle around the triangle.
3. Law of Cosines works with only one angle and three sides in each formula.
4. Law of Cosines works with only one angle and three sides at a time.
5. when you are given all three sides of a triangle and asked to find an unknown angle is called SSS
Noah Lozano Geometry Blog 