1. (5× + 7) + (3x -5)
2. (12x - 4) - (3x - 7)
3. Add 6x² - 7x + 4 and 7x² - 9x + 8
4. Subtract 4x² - 5x - 8 from 6x² - 3x +8
5. (7x² + 3x - 4) - (2x² + 3x -7)​