Question

Solve y=f(x) for x. Then find the input when the output is – 3.

f(x) = 1/2x-3
x=
The input is
when the output is -3.

Answer 1

Given:

`y=f(x)`

`f(x)=(1)/(2)x-3`

To find:

The input when the output is – 3.

Solution:

We have,

`f(x)=(1)/(2)x-3`

Substituting
`f(x)=y`, we get

`y=(1)/(2)x-3` ...(i)

We need to find the input when the output is – 3. It means, we have to find the value of x when
`y=-3`.

Putting
`y=-3` in (i), we get

`-3=(1)/(2)x-3`

`-3+3=(1)/(2)x`

`0=(1)/(2)x`

Multiply both sides by 2.

`0=x`

Therefore, the input is 0 when the output is -3.