- 2.3 – (- 8.9) does it equal -6.6 or x= 2/3=4/6=6/9

x=8/9-6/9=2/9

-2.3 -(-8.9) = -2.3 + 8.9 = +6.6

I don't know what you are doing with the ninths equations, but they are correct. Are they supposed to be related to your first line?