Question

How to solve the function problem for this one?

Answer 1

Answer:

a. f(12) = - 1

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

Step-by-step explanation:

We are given that $f(x)=\frac{1}{3} x-5$ 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

$f(x)=\frac{1}{3} x-5$

plug in 12

$f(12)=\frac{1}{3} (12)-5$

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

$f(x)=\frac{1}{3} x-5$

substitute 4 for f(x) and solve for x

$4=\frac{1}{3}x -5$

add 5 to both sides

$9=\frac{1}{3} x$

multiply both sides by 3

27 = x

And we are done.

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

Answer 2

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