60 points!!! Please answer immediately and the entire page please I will also give you five stars

Answer:
Step-by-step explanation:
9. Correct, D
-3Y + 9X <= 12
3Y - 9X => -12
3Y => -12 + 9X
Y => -4 + 3X
10. D
11. D
12. Correct, B
13. Correct, E
14. A
15. B