The question is
[tex]5\times(-1-3)[/tex]Since we have parenthesis, we do that part 1st.
[tex]\begin{gathered} -1-3 \\ =-4 \end{gathered}[/tex]Two negatives added together gives negative. Now, we multply by 5, to get:
[tex]5\times-4=-20[/tex]Negative times positive is negative.