Answer:
3) 9x² - 5x - 9
Explanation:
Combine like terms
5x² - 9x + 3 + 4x² + 4x - 12 = 5x² + 4x² - 9x + 4x + 3 - 12
= 9x² - 5x - 9
6.3m questions
8.3m answers