Find a formula for the inverse, that is find LaTeX: \displaystyle f^{-1}(x) if LaTeX: \displaystyle f(x)=\frac{7 - 6 x}{6 x + 8} .

LaTeX: \displaystyle f^{-1}(x)=\frac{7 - 8 x}{6 \left(x + 1\right)}