Question

Please help im being timed

Inverse of f(x)=15x+4

Answer 1

`f^(-1)`(x) =

Explanation:

let y = f(x), then rearrange making x the subject

y =
`(1)/(5)`x + 4 ( subtract 4 from both sides )

y - 4 =
`(1)/(5)`x ( multiply both sides by 5 to clear the fraction )

5y - 20 = x

Change y back into terms of x with x =
`f^(-1)` (x) , then

`f^(-1)` (x) = 5x - 20