High Quality Content by WIKIPEDIA articles! The law of sines can be used to compute the remaining sides of a triangle when two angles and a side are known a technique known as triangulation. It can also be used when two sides and one of the non-enclosed angles are known In some such cases, the formula gives two possible values for the enclosed angle, leading to an ambiguous case. The law of sines is one of two trigonometric equations commonly applied to find lengths and angles in a general triangle, the other being the law of cosines.