Question

What is the inverse relation of f(x)=1/5x−4/5?

y=1/5x−4
y=−1/5x+5/4
y=−5x−4
y=5x+4

Answer 1

`y' = 5x + 4`

Explanation:

Given

`f(x) = (1)/(5)x - (4)/(5)`

Required

The inverse relation

`f(x) = (1)/(5)x - (4)/(5)`

Rewrite as:

`y = (1)/(5)x - (4)/(5)`

Swap x and y

`x = (1)/(5)y - (4)/(5)`

Multiply through by 5

`5x = y - 4`

`y = 5x +4`

Rewrite the new function as:

`y' = 5x + 4`