1. **State the problem:** Simplify the expression $$-(3 - 7i) - (-10 - 9i)$$ and write the answer in the form $$a + bi$$. 2. **Recall the rules:** - Distribute the negative sign across the parentheses. - Combine like terms (real parts with real parts, imaginary parts with imaginary parts). 3. **Distribute the negatives:** $$-(3 - 7i) = -3 + 7i$$ $$-(-10 - 9i) = +10 + 9i$$ 4. **Rewrite the expression:** $$-3 + 7i + 10 + 9i$$ 5. **Combine like terms:** Real parts: $$-3 + 10 = 7$$ Imaginary parts: $$7i + 9i = 16i$$ 6. **Final answer:** $$7 + 16i$$