Question

In some cities you can rent a car for ​$15 per day and ​$0.40 per mile. ​(a) find the cost of renting the car for one day and driving 400 miles. ​(b) express the total rental expense as a function of the miles driven​ (x) when the car is rented for one day.

Answer 1

So the cost for renting the car for one day and driving it for 400 miles would be around 15 + 400 (0.4) = 160 + 15 = 175$

To write an expression for a day you can obviously just make up one by putting in x as the number of miles. So to calculate the cost for x miles you can write x * (0.4) and more over at the end we have to add the 15$ so the expression equals to 15 + 0.4 (x)