PLZ HELP I NEED TO TURN THIS IN TODAY

Need on this one asap im almost done with this subject

In stepmber, daniel and justin opened a business. during their first three months of business, their average monthly profit was $51. if during their first month, they lost $29, and during their second month, they gained $115, what was their profit or loss for their third plzzz i will give you 299 points

Manuela solved the equation below. what is the solution to manuela’s equation?