To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $x-5$ and $x-3$ is $\left(x-5\right)\left(x-3\right)$. Multiply $\frac{2s}{x-5}$ times $\frac{x-3}{x-3}$. Multiply $\frac{1}{x-3}$ times $\frac{x-5}{x-5}$.
Since $\frac{2s\left(x-3\right)}{\left(x-5\right)\left(x-3\right)}$ and $\frac{x-5}{\left(x-5\right)\left(x-3\right)}$ have the same denominator, add them by adding their numerators.
