What is the value of y?

(1) 3|x2 – 4| = y – 2

(2) |3 – y| = 11

My question is, that in the

Manhattan Gmat guide, they always ask you to find solutions of the absolute value equation, and then PLUG both values in to the original equation. In case if one of those values dont match up, then that solution can be eliminated. If in either of the equations , we would find a value which could not work, then could we safely count that as sufficiency for that statement, or would we have to still assume that both are possible so not sufficient?

Thanks