Answer:
a=6,-10
Step-by-step explanation:

1. <span>Simplify -9 + -2m to -9 - 2m
-3m = -9 - 2m
2. </span><span>Add </span>2m <span>to both sides
-3m + 2m = -9
3. </span><span>Simplify -3m + 2m to -m
-m = -9
4. </span><span>Multiply both sides by </span><span><span>−<span>1
m = 9
Done! :) our answer is m = 9</span></span></span>