Does this graph represent a function?
a. yes, because each x-value has exactly one corresponding y-value
b. no, because some of the y-values are paired with two x-values
c. no, because there are no closed circles to show here the graph ends.
d. yes, because it touches the y-axis exactly one time.

Barney & noblet customers can choose to purchase a membership for $25 per year members receive 10% off all store purchases 1. how much would a member pay per year if he bought $50 worth of items each year? 2. write a slope-intercept equation that expresses how much a member pays per year using x to represent his purchases per year 3. how much would a member have to spend per year to pay off his membership fee?