Subtract as indicated :
$$\dfrac {8}{3} - \dfrac {5}{9}$$
$$\dfrac{8}{3}-\dfrac{5}{9}$$
Taking L.C.M of $$3$$ and $$9$$ we get $$9$$. So,
$$1^{st}$$ fraction becomes $$\dfrac{8}{3}=\dfrac{8\times3}{3\times3}=\dfrac{24}{9}$$
$$2^{nd}$$ fraction becomes $$\dfrac{5}{9}$$
So,
$$\dfrac{8}{3}-\dfrac{5}{9}=\dfrac{24}{9}-\dfrac{5}{9}=\dfrac{24-5}{9}=\dfrac{19}{9}$$