Find the reference angle of 220 degrees.

Question

a) 40°

b) 50°

c) 20°

d) 140°

Answer 1

220° lies in quadrant 3.

The reference angle is the acute angle with vertex at (0,0) formed by the terminal side of the angle (when drawn in standard position) and the x-axis. So, for the given angle, the reference angle is 220° - 180° = 40°.

Answer 2

a) 40°

Since 220° is greater than 180°but less than 270° the reference angle would be

220 - 180 = 40 because we should use the acute angle in the third quadrant and the terminal side of 220.

Mark's answer above is correct thank you Mark