The person earns $15 for every hour worked at the grocery store. I found this by dividing $60 by 4 since the person makes 60 dollars from a four-hour shift. For y, we can use 60, divide it by 15, and have 4 hours worked. Which is (60,4). We can also use 15 since the person working at the grocery store makes $15 every hour, that would be (15,1). So there are two possible equations that can be used, (60,4), or (15,1).