-6y - 3 = 3 - 6y. Pls solve

I'm so close to finishing all these.

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Question part points submissions used suppose that 100 lottery tickets are given out in sequence to the first 100 guests to arrive at a party. of these 100 tickets, only 12 are winning tickets. the generalized pigeonhole principle guarantees that there must be a streak of at least l losing tickets in a row. find l.