Question

Select all that are measures of angles coterminal with a –60° angle.
–1020°
–780°
–420°
60°
120°
300°
420°
660°

Answer 1

Given: The angle a - 60

To find: Select all that are measures of angles co terminal with a –60° angle.

Solution:

• Now we know that co-terminal angles are the angles which are having same terminal and initial sides.

• Now adding or subtracting k × 360° (where k = 1,2,3...)  to the given angle, we get:

• So, co-terminal angle to -60° angles are:

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

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

                   -60° + 360° = 300°

                   -60° - 360° = -420°    

                   -60° + 2 x 360° = -60° + 720° = 660°

                   -60° -2 x 360° = -60° - 720° = - 780°

Answer:

          So the co-terminal angles are -420°,  660°,  300° and -780°.

Answer 2

Answer:

-420°  

660°

300°  

-780°

second one:

- 575

- 215

505

865

Step-by-step explanation: