1. **State the problem:** Simplify the expression $$(2x^2 - 7x + 1) - (-5x^2 + x - 9)$$. 2. **Formula and rules:** When subtracting polynomials, distribute the minus sign to each term inside the parentheses and then combine like terms. 3. **Distribute the minus sign:** $$ (2x^2 - 7x + 1) - (-5x^2 + x - 9) = 2x^2 - 7x + 1 + 5x^2 - x + 9 $$ 4. **Combine like terms:** - Combine $x^2$ terms: $$2x^2 + 5x^2 = 7x^2$$ - Combine $x$ terms: $$-7x - x = -8x$$ - Combine constants: $$1 + 9 = 10$$ 5. **Final simplified expression:** $$7x^2 - 8x + 10$$ **Answer:** A) $7x^2 - 8x + 10$