I set it in a big problem. Since you know that all the angles of a triable add up to 180, m<a + m<b + m<c = 180, plug in equations/values (36) + (3x+12) + (3x+18) = 180, subtract 36 3x+12 + 3x+18 = 144, combine like terms, 6x+30 = 144, subtract 30, 6x=114, divide by 6, x=19. Plug in X to the equations for m<b and m<c
