You need to be able to do these yourself. Posting every extra credit problem on here is only going to be detrimental to your mathematical ability later.

What does it mean for a line to be parallel? Work through it.

First, get that in standard form:

y = 3x - 5

Do you see that 3 is the SLOPE (y = mx + b) and -5 is the y-intersect?

Thus, what is a parallel line? Do you agree a parallel line has to have the same slope, and thus y = 3x + c is a parallel line? Since it has to pass through the origin, y = 3x is your answer (essentially, y = 3x + 0).