Question

For the function, f(x) =1/4 x - 2, find x if f(x) = -1.

A. x=-9/4
b=x=4
b=x=1/4
x=-7/4

Answer 1

B: X = 4

Explanation:

-1 = 1/4 X- 2

1 = 1/4 X

4 = X

Answer 2

For this case we have a function of the form
`y = f (x)`, where
`f (x) = \frac {1} {4} x-2`

We want to find the value of "x" when the function has the value of -1, that is, when
`y = f (x) = - 1`

So:

`f (x) = \frac {1} {4} x-2 = -1\\\frac {1} {4} x-2 = -1`

We clear "x":

We add "2" to both sides of the equation:

`\frac {1} {4} x-2 + 2 = -1 + 2\\\frac {1} {4} x = 1`

We multiply by "4" on both sides of the equation:

`\frac {1} {4} x * 4 = 1 * 4\\x = 4`

So, when
`y = -1`then
`x = 4`

Answer:

`x = 4`