A car rental agency charges ​$35

per day to rent a car and ​$14.95
per day for a global positioning system​ (GPS). Customers are charged for their full tank of gas at ​$3.40
per gallon. A car has a 19
gallon tank and a GPS.
a) Write a function rule for the total bill b as a function of the days d the car is rented.
​b) What is the bill for a 9 day​ rental?

1 answer

cost(d) = 35d + 14.95d + 19(3.40)
= 49.95 d + 64.60
where d is the number of days

So for 9 days, replace d with 9 and evaluate.