Linda is doing car wash with her teammates to collect money for their trip. They can get $12 for the car that they wash. In order to start their work, they spent $155 to buy

supplies needed for the work.

Part A:

Create a function f(c) to represent the profit that they make for washing c cars.

f(c) =

(b)

Part B:

Use the function rule that you created on Part A to find the value of f '(145)

f-? (145)

9514 1404 393

  (a) f(c) = 12c -155

  (b) f⁻¹(145) = 25

Step-by-step explanation:

(a) Profit is the difference between revenue (12c) and cost (155). The profit function is ...

  f(c) = 12c -155

__

(b) The number of cars Linda's team must wash to achieve a profit of $145 is found from ...

  145 = 12c -155

  300 = 12c . . . . . . add 155

  25 = c . . . . . . . . . divide by 12

  f⁻¹(145) = 25 . . . . the team must wash 25 cars for a profit of $145