Question: User: -4y -4z
1. **State the problem:** Simplify the expression $$-4y - 4z$$.
2. **Identify common factors:** Both terms have a common factor of $$-4$$.
3. **Factor out the common factor:**
$$-4y - 4z = -4(y + z)$$
4. **Explanation:** Factoring means taking out the greatest common factor from each term. Here, $$-4$$ is common in both $$-4y$$ and $$-4z$$, so we factor it out.
5. **Final answer:**
$$-4(y + z)$$