Choose the equation you can use to solve the following problem.

Jamal spends $15 on a pair of soccer shorts. He has $10 left. How much money did he have before buying the shorts?
m represents the money Jamal had to start.
m + 10 = 15
m – 10 = 5
m + 15 = 40
m – 15 = 10

m - 15 = 10