Answer:
y = -3x
Explanation:
We can see that the given line:

is in point-slope form:
,
where
is a point on the line.
Using this knowledge, we can identify the slope as
.
Parallel lines have the same slope. Therefore, to answer this question, we can create any line in slope-intercept form with a slope of -3.
One answer could be:
y = -3x