Sophia has made mistake in step 6. She should have divided each side by 3 instead of multiplying.
The given function is [tex]f(x)=\dfrac{3x+4}{8}[/tex].
It is required to calculate the inverse of the function.
So, the steps involved in finding the inverse of the function will be,
Step 1:
Write the given function as,
[tex]f(x)=\dfrac{3x+4}{8}[/tex]
Step 2:
Change the function f(x) to y as,
[tex]y=\dfrac{3x+4}{8}[/tex]
Step 3:
Switch x and y as,
[tex]x=\dfrac{3y+4}{8}[/tex]
Step 4:
Multiply each side of the equation by 8 as,
[tex]8x=8\dfrac{3y+4}{8}\\8x=3y+4[/tex]
Step 5:
Now, subtract 4 from each side of the equation as,
[tex]8x-4=3y+4-4\\8x-4=3y[/tex]
Step 6:
Now, it is required to divide each side by 3.
[tex]\dfrac{8x-4}{3}=\dfrac{3y}{3}\\\dfrac{8x-4}{3}=y[/tex]
Step 7:
Now, replace y with [tex]f^{-1}(x)[/tex] as,
[tex]\dfrac{8x-4}{3}=f^{-1}(x)[/tex]
So, the required inverse function should be [tex]f^{-1}(x)=\dfrac{8x-4}{3}[/tex].
Therefore, Sophia has made mistake in step 6. She should have divided each side by 3 instead of multiplying.
For more details, refer to the link:
https://brainly.com/question/19606498