What would B slash, I'll just call it a slash right over here, what would B minus A be? What would B minus A be, which we could also write as B minus A. What would this be equal to? Well, just going back, we could view this as all of the things in B with all of the things in A taken out of it or all of the things, the complement of A that happens to be in B. Let's think of it as the set B with all the things in A taken out of it. We start with set B, we have a 17, but a 17 is in set A so we have to take the 17 out. Then we have a 19, but there's a 19 in set A so we have to take the 19 out.