Final answer:
The inequality 5x + 3y ≤ 450 represents all possible combinations of x, the number of quesadillas sold, and y, the number of burritos sold.
Step-by-step explanation:
To represent all possible combinations of the number of quesadillas sold and the number of burritos sold, we can use the inequality 5x + 3y ≤ 450. Here, x represents the number of quesadillas sold and y represents the number of burritos sold. The left-hand side of the inequality represents the total amount earned from selling quesadillas and burritos, which should be less than or equal to $450.