User blog comment:KATANAGOD/Content Collection 1 coming to PC/@comment-67.6.21.56-20120418184516/@comment-1630756-20120418190726

...Not really the place for asking, but since you did then:
 * If you have the two other angles, then simply add them together and subtract it from 180˚ to get the third. (180 - a - b = c)
 * If you have lengths of two sides and one angle, you can use the sine rule. (A/sin a = B/sin b)
 * If you have the lengths of three sides and no angles, you can use the cosine rule instead. (a2 = b2 + c2 - 2 x b x c x cos a)

Hope that helps.