Question

Which function is the inverse of f(x) = -5x-4?

1
4
1
4
O 8(x)3x -
F () --3x+
O F1(x) = -4x+5
Of '(x) = 4x+4

Answer 1

`\huge\boxed{f^(-1)(x) = -(x+4)/(5)}`

Explanation:

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

Replace y = f(x)

`y = -5x-4`

Exchange values of x and y

`x = -5y -4`

Solve for y

`x = -5y - 4`

Adding 4 to both sides

`x + 4 = -5y`

Dividing both sides by -5

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

Replace y =
`f^(-1)(x)`

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

Answer 2

The inverse is -1/5x -4/5

Explanation:

f(x) = -5x-4

y = -5x-4

Exchange x and y

x = -5y -4

Solve for y

Add 4 to each side

x+4 = -5y

Divide by -5

-1/5x -4/5 = -5y/-5

-1/5x -4/5 = y

The inverse is -1/5x -4/5