Negative numbers signify the favorite on a moneyline bet. The negative number indicates how much you'd need to bet to win $100. If there's a positive number, you're looking at the underdog, and the number refers to the amount of money you'll win if you bet $100.
A both teams to score and win accumulator is a new and very popular type of bet. For us to win the bet, we need both teams to score and the team we select to win.