Final answer:
The equation showing the amount of potato salad remaining, y, after filling x number of 2.5-cup containers is y = 30 - 2.5x.
Step-by-step explanation:
Isaac works at a deli and is filling 2.5-cup to-go containers with a 30-cup batch of potato salad. The equation to represent the number of cups of potato salad remaining, y, as a function of the number of to-go containers filled, x, is y = 30 - 2.5x. Each time Isaac fills a container, he uses 2.5 cups of the salad, so the remaining amount decreases by 2.5 cups per container filled. To find the remaining quantity after x containers have been filled, you multiply the number of containers, x, by 2.5 and subtract this from the original 30 cups.