-1/9+-5/9=
When you are adding a negative number, the operation turns into subtraction:
-1/9-5/9=[tex]\frac{-1-5}{9}[/tex][tex]=-\frac{6}{9}=-\frac{2}{3}[/tex]
Really, it's just subtraction. The simplest form is -2/3, which is equal to -0.66667.
I hope this helps :)
