LAW OF SINESin A = Sin B = Sin C

a b c

 

A, B and C are angles.

a, b and c are the sides opposite their angles.

 

 

Use when:

you have 2 angles and a side (AAS or ASA)

you have 2 sides and an opposite angle (SSA)

LAW OF COSINE

a² = b²+ c² - 2bcCos Ab² = a² + c² - 2acCos Bc² = a² +b² - 2abCosC Use when:you have the measures of two sides and the included angle (SAS)you have 3 sides (SSS)

Find angles from largest to smallest. To Find Angle Measureuse 2nd Trig function (Sin/Cos/Tan), 2nd answer (or enter)