Answer:
a = - 4, b = 5
Step-by-step explanation:
Expand the left side, then compare the coefficients of like terms.
- 3(2x² + ax + b)
= - 6x² - 3ax - 3b, compare to - 6x² + 12x - 15
Compare coefficients of x- terms
- 3a = 12 ( divide both sides by - 3 )
a = - 4
Compare constant terms
- 3b = - 15 ( divide both sides by - 3 )
b = 5
