Answer:
x² + 10x - 24
Step-by-step explanation:
3x² - 12 + (x - 4)(2 - x) - (x² - 4x + 4)
= 3x² - 12 + (2x - x² - 8 + 4x) - x² + 4x - 4
= 3x² - 12 + 2x - x² - 8 + 4x - x² + 4x - 4
= x² + 10x - 24
