1. The problem statement, all variables and given/known data (x+y)(x'z' + z)(y'' + x'z') = x'y 2. Relevant equations Boolean Identities 3. The attempt at a solution (x+y)(x'z' + z)(y''(x'+z') -- DeMorgan's Theorem (x+y)(x'z' + z)(y(x'+z')) -- Involution Law (x+y)(z+x')(y(x'+z')) That's all I've gotten so far. I'm not sure how to get rid of (x+y) term. I was also thinking of using the distributive law on (y(x'+z'), but I couldn't find any theorem or postulate for it. Any help is greatly appreciated!