Ah, so without giving you the answer, I'll help you. Because the question says "with an equivalent of 'y'", you're pretty much going to substitute any number you want in for y, and solve. The answer that has both sides equal to the same number, is correct.
For example:
If I had 3y+7 and 4y + 6
You're going to substitute any number you want. I chose 4 for example.
3(4) + 7= 19
4(4) +3=19
This would be your answer because both expressions have the same number as the outcome.