f(x)= 5(x+4) -6
To find inverse we follow the steps given below
step 1: replace f(x) with y
y= 5(x+4) - 6
step 2: replace x with y and y with x
x= 5(y+4) -6
step 3: solve for y
x= 5(y+4) -6
x + 6 = 5(y+4)
x + 6 = 5y +20
x - 14 = 5y
[tex]\frac{x-14}{5} = y[/tex]
step 4: replace y with f^-1(x)
[tex]f^{-1}(x) = \frac{x-14}{5}[/tex]
We got the inverse function
solve for the inverse function when x=19.
we replace 19 for x in f^-1(x)
[tex]f^{-1}(19) = \frac{19-14}{5}[/tex]= 1
[tex]f^{-1}(19) =1 [/tex]