Question

Which of the following is the function of f(x)?

Answer 1

`\boxed{f(x) = 8(x-3)}`

Explanation:

`y=(x)/(8) +3`

Switch variables.

`x=(y)/(8) +3`

Make y as subject.

Subtract 3 from both sides.

`x-3=(y)/(8)`

Multiply both sides by 8.

`8(x-3)=y`

Answer 2

f(x) = 8(x-3)

Explanation:

F^ -1 ( x) = x/8 +3

Let y = x/8+3

To find the inverse

Exchange x and y

x = y/8+3

Solve for y

x-3 = y/8+3-3

x-3 = y/8

Multiply each side by 8

8(x-3) = y/8 * 8

8(x-3) = y

The inverse of the inverse is the function so

f(x) = 8(x-3)