There is another, more mathematical way:

If no zero values in your columns:

select *, 5-Positives as Negatives

from (select *,(sign(col1)+sign(col2)+sign(col3)+sign(col4)+sign(col5)+5)/2 Positives

from tablename) sn

And, if there are zero values:

select col1, col2, col3, col4, col5

,(s1+abs(s1)+s2+abs(s2)+s3+abs(s3)+s4+abs(s4)+s5+abs(s5))/2 as Positive

,abs((s1-abs(s1)+s2-abs(s2)+s3-abs(s3)+s4-abs(s4)+s5-abs(s5))/2) as Negative

from (select *,sign(col1) s1,sign(col2) s2,sign(col3) s3,sign(col4) s4,sign(col5) s5

from tablename) sn