help please, i will give brainless to who helps me out

Help Please I Will Give Brainless To Who Helps Me Out class=

Answer :

9. Answer:

30

10. Answer:

2

11. Answer:

4

12. Answer:

4

13. Answer:

-1

Tip:

Use photomath, its an app

9. x = 30

10. x = 2

11. x = 4

12. x = 2

13. x = -1