You are at a book store and you are allowed to buy 9 books. You have already selected 3 books. Find the possible amount of books you can still select.
The total amount of books you select must be less than or equal to 9. The amount of books you will spend can be modeled by b + 3 because you have already selected 3 books. The inequality representing this situation is b + 3 ≤ 9