The function that models the cost of renting a car for x days has the following format:
y = a + bx
In which a is the one-time insurance charge and b is the daily cost.
Amanda rents each of her cars for a one-time $10.00 insurance charge plus $4.50 per day.
This means that a = 10, b = 4.5
So
y = 10 + 4.5x
The graphic is a line starting at y = 10, and increasing 4.5 units per day(per unit of x). So
