1. **State the problem:** Find the limit $$\lim_{x \to 0} \frac{x + a - a}{x}$$ where $a$ is a constant. 2. **Simplify the expression:** Notice that $a - a = 0$, so the expression simplifies to $$\frac{x}{x}$$. 3. **Evaluate the limit:** For $x \neq 0$, $$\frac{x}{x} = 1$$. 4. **Conclusion:** As $x$ approaches 0, the expression approaches 1. Therefore, $$\lim_{x \to 0} \frac{x + a - a}{x} = 1.$$