Answer:
Solution given:
f(x) = [tex]\frac{1}{9}[/tex] x-2
let f(x)=y
y = [tex]\frac{1}{9}[/tex] x-2
interchanging role of x and y
x= [tex]\frac{1}{9}[/tex] y-2
x+2= [tex]\frac{1}{9}[/tex] y
y=9(x+2)
y=9x+18
So
F-¹(x)=9x+18
and
F-¹(-1)=9*-1+18=-9+18=9