Understanding:
[Q1] f(x) represents the money Philip owes his friend while x being the time in months. When x was zero, Philip owed his friend a total of $1080. Therefore, the answer is D.
[Q2] You can calculate the slope by using the following formula [tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex], by using any 2 points on the graph we can easily calculate the slope.
[tex]m=\frac{810-1080}{6-0}=\frac{-270}{6}=-45[/tex]
Solutions:
[Q1] D. Philip paid a total of $1080 for the car
[Q2] [tex]m=-45[/tex]
[Q3] The slope represents the amount Philips pays his friend monthly.
