1. **State the problem:** Simplify the expression $-(-5.8 d - 3 f - 4)$. 2. **Recall the rule:** The negative sign outside the parentheses means we multiply each term inside by $-1$. 3. **Apply the rule:** $$-(-5.8 d - 3 f - 4) = (-1) \times (-5.8 d) + (-1) \times (-3 f) + (-1) \times (-4)$$ 4. **Simplify each term:** $$= 5.8 d + 3 f + 4$$ 5. **Final answer:** $$5.8 d + 3 f + 4$$ This means the negative sign outside the parentheses changes the signs of all terms inside, turning them positive.