Probably looks like this: \(\frac{\sqrt{23}}{3}\)
Just put 23/9 in fraction form and square root the top and bottom separately.
There are no whole numbers that desribe a ratio that exactly equals sqrt(23/9) since it is an irrational number, so you must use sqrt(23) on top, and of courae sqrt(9) is just 3.
Hope this helps. -LambLamb