like terms would just be ones with the same variables
1. 7m, 20m, 5m
2. 13, 6, 2
3. 21bc, 8bc, 15bc
4. 27y, -6y, 9y
5. 45r, -7r, 5r
next section
6. 9r
7. 7r-8
8. -19r — 22p
9. 8r + 9p -7
10. 0
11. -19p — 2r
12. 9/4 r
13. 9r
14. 7/3p
ps. u should make questions that are long (like this) more points so ppl might be more willing to help (: