Answer:
Do you still need an answer? If so, B!
Explanation:
Just by looking at the equation you can see the addition symbols. Since there are also letters, you can use that information to help you solve the answer using the key word: Commutative.
For Example: If Lily needs $40 and she already has $30 how many more dollars does she need?
Answer: m-$30=$40 m=$10