#### Answer

$y=2$

#### Work Step by Step

If the slope equals to $0$, we can surely state that the line is horizontal.
The equation of a horizontal line is always in the form of:
$y=a$, where $a$ is constant.
Here, the point given is $(-3,2)$, which is on the line.
For this point, $y=2$ and this should be true for the other points on the line.
The equation is, therefore:
$y=2$