I think the answer would be 45x+20+45y. That is because Bess and Gina both earn $45 per week. We don't know how many weeks they worked for so that is x for Bess and y for Gina. But then Bess earns $20 bonus so you would add that to how much she already earned. They want to know the total amount of money they both earned together. So that would be 45x+20 (Bess) plus 45y (Gina).
