Tolong jawab no 1,5,14,18,20

1. m+9=18
m = 18-9
m =9

5. -7m = 21
m = - 21 : 7
m = -3

14. 2 - 8m = -62
-8m = -62 - 2
-8m = -64
m = -64 : -8
m = 8

18. 3 = 28 + 5m
3 - 28 = 5m
5m = -25
m = -25 : 5
m = -5

20. 49 - 2m = 9
2m = 49 - 9
2m = 40
m = 40 : 2
m = 20