To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $a-3$ and $a+2$ is $\left(a-3\right)\left(a+2\right)$. Multiply $\frac{2}{a-3}$ times $\frac{a+2}{a+2}$. Multiply $\frac{3}{a+2}$ times $\frac{a-3}{a-3}$.
Since $\frac{2\left(a+2\right)}{\left(a-3\right)\left(a+2\right)}$ and $\frac{3\left(a-3\right)}{\left(a-3\right)\left(a+2\right)}$ have the same denominator, add them by adding their numerators.
Since $\frac{5a-5}{\left(a-3\right)\left(a+2\right)}$ and $\frac{4a-7}{\left(a-3\right)\left(a+2\right)}$ have the same denominator, subtract them by subtracting their numerators.
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $a-3$ and $a+2$ is $\left(a-3\right)\left(a+2\right)$. Multiply $\frac{2}{a-3}$ times $\frac{a+2}{a+2}$. Multiply $\frac{3}{a+2}$ times $\frac{a-3}{a-3}$.
Since $\frac{2\left(a+2\right)}{\left(a-3\right)\left(a+2\right)}$ and $\frac{3\left(a-3\right)}{\left(a-3\right)\left(a+2\right)}$ have the same denominator, add them by adding their numerators.
Since $\frac{5a-5}{\left(a-3\right)\left(a+2\right)}$ and $\frac{4a-7}{\left(a-3\right)\left(a+2\right)}$ have the same denominator, subtract them by subtracting their numerators.