Answer:
2) 168
Step-by-step explanation:
It is a function. It passes the vertical line test, meaning for each x there's at most one y.
When x=2 we see y=-3 as (2,-3) is a point on the graph
50.1 repeateding because that is the only positive number
He would have 21 before he bought the 10 stamp because 31-10=21
