Question

What is the inverse function of d(x)= 2x-4

Answer 1

Formula for inverse function:
$d^{-1}(y)=?\\y=2x-4\\2x=y+4\\x= \frac{y+4}{2}\\ d^{-1}(y)= \frac{y+4}{2}$

Answer 2

$y=2x-4 \\ Replace \ x \ by \ y:\\ x=2y-4\\ Isolate \ y:\\ 2y=x+4\\ y=\frac{x+4}{2}\\ \\ \boxed{d^{-1}(x)=\frac{x+4}{2}}$