Answer
$f^{-1}(x)=\frac{-4x-3}{x-2}$
Work Step by Step
$f(x)=\frac{2x-3}{x+4},$
$y=\frac{2x-3}{x+4},$
a. $x=\frac{2y-3}{y+4},$
$x(y+4)=2y-3,$
$xy+4x=2y-3,$
$xy-2y=-4x-3,$
$y(x-2)=-4x-3,$
$y=\frac{-4x-3}{x-2}=f^{-1}(x),$
b. Domain of $f(x)$ is $x\in\mathbb{R} \ne -4$ and Domain of $f^{-1}(x)$ is $x\in\mathbb{R} \ne 2$