To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $5$ and $3$ is $15$. Multiply $\frac{x-1}{5}$ times $\frac{3}{3}$. Multiply $\frac{2x-7}{3}$ times $\frac{5}{5}$.
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of $5$ and $3$ is $15$. Multiply $\frac{x-1}{5}$ times $\frac{3}{3}$. Multiply $\frac{2x-7}{3}$ times $\frac{5}{5}$.
