6x² - x - 15
Rewrite the expression by writing -x as a difference:
6x² + 9x - 10x - 15
Factor out 3x from the expression:
3x * (2x + 3) - 10x - 15
Factor out -5 from the expression:
3x * (2x + 3) - 5 * (2x + 3)
Factor out the expression:
(2x + 3) * (3x - 5)
Therefore the answer to your question would be:
D) 3x - 5