Answer:
5x² + 5x - 7
Step-by-step explanation:
Step 1: Write equation
(-x² - x) + (6x² + 6x - 7)
Step 2: Combine like terms (x²)
5x² - x + 6x - 7
Step 3: Combine like terms (x)
6x^2 + 6x - 7 - x^2 - x
5x^2 + 5x - 7
