Question

PLZ HELP: Write the inverse function for the function, ƒ(x) = 1/2x + 4. Then, find the value of ƒ -1(4). Type your answers in the box.

Answer 1

Answer:

see explanation

Step-by-step explanation:

let y = f(x) and rearrange making x the subject, that is

y = $\frac{1}{2}$ x + 4 ( multiply through by 2 to clear the fraction )

2y = x + 8 ( subtract 8 from both sides )

2y - 8 = x

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

$f^{-1}$(x ) = 2x - 8

$f^{-1}$(4) = 2(4) - 8 = 8 - 8 = 0