All the angles of a triangle are equal to 180°, so since we are given 120°, that means that both angles together equal 60°. Set the equations equal to 60°, so (x+16)+x=60°. Add like terms and get x to itself, so subtract 16 from 60 and add the x's together. You should get 2x=44°. Divide 44 by 2 and you get x=22°.