[tex]Negative*Negative=Positive[/tex]
[tex]Positive*Positive=Positive[/tex]
[tex]Negative*Positive=Negative[/tex]
Let the negative be (-) and positive be represented as (+)
[tex](-)*(-)*(+)*(+)*(+)[/tex]
We know that [tex]Negative*Negative=Positive[/tex]
So we simplify this to:
[tex](+)*(+)*(+)*(+)[/tex]
And this is a positive value.