. Randall had $120 set aside for lunches. He spends $15 each week. The graph shows this relationship, where x is the number of weeks and y is the amount of lunch money left.
a. Highlight or circle the relevant part of the graph and explain your reasoning.
b. Write the slope-intercept form of the equation representing this situation.

c. When will Randall run out of money? Where is this information found on the graph?