Question

What is the positive and negative angle that is coterminal with $ 120^\circ $ ?

Answer 1

Hint: Coterminal angles can be defined as the angles which share the same initial side and the terminal sides. It is as simple as adding or subtracting the $ 360^\circ $ from each angle which depends on whether the given angles are in the measure of degrees or the radians.

Complete step-by-step answer:
Given measure of angle is $ 120^\circ $
Add $ 360^\circ $ to the given angle
 $ = 120^\circ + 360^\circ $
Simplify find the addition of the two angles
 $ = 480^\circ $ ….. (A)
Similarly,
Subtract $ 360^\circ $ to the given angle
 $ = 120^\circ - 360^\circ $
Simplify find the addition of the two angles
 $ = - 240^\circ $ ….. (B)
Hence, the positive and the negative coterminal angles are \[480^\circ \]and $ - 240^\circ $
This is the required solution.

Note: An angle can be formed by using two lines or the line segments or the rays with the common meeting point. Angles are measured in an anti-clockwise manner by using the protractor in degrees.