# How do you find the value of f(3), if f(x)=3x-4?

Mar 12, 2018

$f \left(3\right) = 5$

#### Explanation:

Simply substitute the value of $3$ given. In other words, $f \left(3\right)$ is the function of $f \left(x\right)$, however, in this case, $x$ is $3$

$f \left(3\right) = 3 \left(3\right) - 4$

Distribute $3$ through the parenthesis

$f \left(3\right) = 9 - 4$

Simplify

$f \left(3\right) = 5$

Mar 12, 2018

$f \left(3\right) = 5$

#### Explanation:

How you start the equation is by plugging $3$ into both of the $x$'s in the problem to make it:

$f \left(3\right) = 3 \left(3\right) - 4$

Next, you multiply the $3 \left(3\right)$ to get $9$ and subtract $4$. So in the end, you leave the $f \left(3\right)$ and $9 -$4 is $5$, so the $y$ in the equation is $5$.

The answer would be written as

$f \left(3\right) = 5$