Take a look at what you get when you divide 1/9.
\(\ \ \ 0.11...\\9\overline{)1.0000}\\\sp{ \ \ \ -9}\\\sp{\ \ \ \ \ 10}\\\sp{\ \ \ \ -9}\\\sp{\ \ \ \ \ 10...}\)
So when you divide 6/9, you would get 0.66666....
6 and 9 are both divisible by 3, so 6/9 = 2/3.
Therefore \(8.\overline{6}=\boxed{8\frac{2}3}\).
