1. **State the problem:** Simplify the expression $$(63x^2 + 9x) - (5x + 40)$$. 2. **Apply the distributive property:** Remove the parentheses by distributing the minus sign to the second group: $$63x^2 + 9x - 5x - 40$$ 3. **Combine like terms:** Combine the terms with $x$: $$9x - 5x = 4x$$ 4. **Write the simplified expression:** $$63x^2 + 4x - 40$$ 5. **Final answer:** $$\boxed{63x^2 + 4x - 40}$$