#### Answer

$x=4$

#### Work Step by Step

We set up a proportion, using $\frac{x_1}{y_1}=\frac{x_2}{y_2}$, where $x_1$ and $y_1$ represent the $x$ and $y$ values in the problem, and $x_2$ and $y_2$ represent the new values.
In this case, we don't know what $x_2$ is, so we will represent that as $x$.
We set up the proportion to get
$\frac{2}{6}=\frac{x}{12}$.
Cross multiplying gives
$6x=24$.
To isolate $x$, we divide both sides by 6, giving
$x=4$.