For this case we must find the inverse of the following function:
[tex]f (x) = 2x + 5[/tex]
Then, we follow the steps:
We change [tex]f (x)[/tex]by y:
[tex]y = 2x + 5[/tex]
We exchange the variables:
[tex]x = 2y + 5[/tex]
We clear the variable "y":
[tex]x-5 = 2y\\y = \frac {x-5} {2}[/tex]
We change y for [tex]f^{-1}(x):[/tex]
[tex]f^{-1}(x) = \frac {x-5} {2}[/tex]
Answer:
[tex]f^{-1}(x) = \frac {x-5} {2}[/tex]