Which rotation about the origin?

Compare the coordinates. 180°: both signs change. 90° clockwise: (x, y) goes to (y, −x). 90° counterclockwise: (x, y) goes to (−y, x).

1. A point is rotated about the origin from (1, −6) to (6, 1). Which rotation was it? Write 90cw, 90ccw or 180.
2. A point is rotated about the origin from (5, 1) to (−1, 5). Which rotation was it? Write 90cw, 90ccw or 180.
3. A point is rotated about the origin from (−8, 5) to (−5, −8). Which rotation was it? Write 90cw, 90ccw or 180.
4. A point is rotated about the origin from (−4, −2) to (−2, 4). Which rotation was it? Write 90cw, 90ccw or 180.
5. A point is rotated about the origin from (7, −8) to (−8, −7). Which rotation was it? Write 90cw, 90ccw or 180.
6. A point is rotated about the origin from (5, 3) to (−5, −3). Which rotation was it? Write 90cw, 90ccw or 180.
7. A point is rotated about the origin from (9, 6) to (6, −9). Which rotation was it? Write 90cw, 90ccw or 180.
8. A point is rotated about the origin from (5, 7) to (7, −5). Which rotation was it? Write 90cw, 90ccw or 180.
9. A point is rotated about the origin from (−7, −2) to (2, −7). Which rotation was it? Write 90cw, 90ccw or 180.
10. A point is rotated about the origin from (−11, −4) to (−4, 11). Which rotation was it? Write 90cw, 90ccw or 180.
11. A point is rotated about the origin from (3, −4) to (−3, 4). Which rotation was it? Write 90cw, 90ccw or 180.
12. A point is rotated about the origin from (−7, −8) to (8, −7). Which rotation was it? Write 90cw, 90ccw or 180.
13. A point is rotated about the origin from (−15, 14) to (15, −14). Which rotation was it? Write 90cw, 90ccw or 180.
14. A point is rotated about the origin from (3, −15) to (15, 3). Which rotation was it? Write 90cw, 90ccw or 180.
15. A point is rotated about the origin from (−6, −11) to (11, −6). Which rotation was it? Write 90cw, 90ccw or 180.
16. A point is rotated about the origin from (−1, −14) to (14, −1). Which rotation was it? Write 90cw, 90ccw or 180.
17. A point is rotated about the origin from (14, −2) to (2, 14). Which rotation was it? Write 90cw, 90ccw or 180.
18. A point is rotated about the origin from (−9, 10) to (9, −10). Which rotation was it? Write 90cw, 90ccw or 180.
19. A point is rotated about the origin from (6, −18) to (−6, 18). Which rotation was it? Write 90cw, 90ccw or 180.
20. A point is rotated about the origin from (13, 18) to (−18, 13). Which rotation was it? Write 90cw, 90ccw or 180.