Question

Select all that are measures of angles coterminal with a –60° angle.

Answer 1

Answer:

Co-terminal angles from given options are 300° , - 420°,  660°,   - 780°.

Step-by-step explanation:

Co-terminal angles are angles that have same terminal and initial sides.

We can find co-terminal angles by simply adding or subtracting k ×360° (where k = 1,2,3...)  to the given angle.

So, co-terminal angle to -60° angles

- 60° + 360° = 300°

- 60° - 360° = - 420°    

- 60° + 2×360° =  - 60° + 720° = 660°

- 60° -2×360° = - 60° - 720° = - 780°

- 60° + 3×360° =  - 60° + 1080° = 1020°

- 60° -2×360° = - 60° - 1080° = - 1140°

Thus, Co-terminal angles from given options are 300° , - 420°,  660°,   - 780°.

 

Answer 2

-60

-60 + 360 = 360 -60 = 300

-60 + 360 + 360 = -60 +720 = 720 - 60 = 660

Also for the negative.

-60 -360 = -420

-60 -360 -360 = -780

-780°, -420°, 300°, 660°