Question

How to solve the function problem for this one?

Answer 1

For a plug in 12 for x:

f(12) = 1/3(12)-5

f(12) = 4-5

f(12) = -1

For b plug in 4 for x:

f(4) = 1/3(4)-5

f(4) = 4/3 -5

f(4) = 0.75-5

f(4)= -4.25

Answer 2

a. f(12) = - 1

b. x = 27 when f(x) = 4

Explanation:

We are given that
`f(x)=(1)/(3) x-5` and we want to find f(12) and f(x) = 4

To find f(12) we simply plug in 12 into x and evaluate it

`f(x)=(1)/(3) x-5`

plug in 12

`f(12)=(1)/(3) (12)-5`

multiply 12 and 1/3 to get 4

`f(12)=4-5`

subtract 5 from 4 to get -1

`f(12)=-1`

Now we want to find the value of x when f(x) = 4

To do this we substitute 4 for f(x) and solve for x

`f(x)=(1)/(3) x-5`

substitute 4 for f(x) and solve for x

`4=(1)/(3)x -5`

add 5 to both sides

`9=(1)/(3) x`

multiply both sides by 3

27 = x

And we are done.

So f(12) = -1 and x = 27 when f(x) = 4