Consider f(x)=y.
[tex]\begin{gathered} f(x)=y \\ x=f^{-1}(y) \end{gathered}[/tex]
Simplify the equation f(x)=y to obtain the value of x in terms of y.
[tex]\begin{gathered} f(x)=y \\ \frac{10}{9}x+11=y \\ \frac{10}{9}x=y-11 \\ 10x=9y-99 \\ x=\frac{9y-99}{10} \end{gathered}[/tex]
So inverse of function is,
[tex]f^{-1}(x)=\frac{9y-99}{10}[/tex]
Correct nswer is A part.
