Which expression can be used to determine the reference angle for an angle, x , measuring 150 degrees ?

An angle of 150° lies in Quadrant II. The reference angle in Quadrant II is found by subtracting the angle from 180°, so use 180° − x; for x = 150°, this gives a 30° reference angle. The correct choice is “180 degrees minus x.”

AI-written and checked against the verified answer.