Answer
$\frac{1}{18}$
Work Step by Step
To subtract fractions with unlike denominators, we must first make them have the same denominator. We do this by multiplying by fractions that are equivalent to $1$.
$\frac{5}{9}\times\frac{10}{10}=\frac{50}{90}$
$\frac{5}{10}\times\frac{9}{9}=\frac{45}{90}$
We can now subtract the two fractions by subtracting the numerators and putting it over the denominator.
$\frac{50}{90}-\frac{45}{90}=\frac{5}{90}$
We divide by $\frac{5}{5}$ to simplify: $\frac{5}{90}\div\frac{5}{5}=\frac{1}{18}$