Question

Marissa wants to join a video game club. She will be charged a flat fee to join the club and will also pay for each game she purchases. The total amount she can expect to pay, in dollars, can be estimated using the function f ( x ) = 20 x + 90 , where x is the number of games purchased. What is the inverse of this function?

Answer 1

The inverse of the function f(x) = 20x + 90 is found by swapping x and f(x) and solving for the new x, resulting in the inverse function f^-1(x) = (x - 90) / 20.

Step-by-step explanation:

The function given, f(x) = 20x + 90, represents the total amount Marissa can expect to pay for video games, where x is the number of games purchased. To find the inverse of this function, we switch x and f(x) and solve for the new x. Here are the steps:

• Replace f(x) with y: y = 20x + 90.
• Switch x and y: x = 20y + 90.
• Solve for y: y = (x - 90) / 20.

The inverse function can then be written as f-1(x) = (x - 90) / 20.