1. **State the problem:** Simplify the expression $\sqrt{5} + \sqrt{5}$.\n\n2. **Recall the rule:** When adding like terms, you add their coefficients. Here, $\sqrt{5}$ is like a term, so $\sqrt{5} + \sqrt{5} = 2 \times \sqrt{5}$.\n\n3. **Apply the rule:**\n$$\sqrt{5} + \sqrt{5} = 2\sqrt{5}$$\n\n4. **Explanation:** Since both terms are the same radical, you can treat $\sqrt{5}$ as a variable and add the coefficients (1 + 1 = 2).\n\n**Final answer:** $2\sqrt{5}$