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