Answer:
12x³ - 7x² + 11x + 14
Step-by-step explanation:
Each term in the second factor is multiplied by each term in the first factor, that is
3x(4x² - 5x + 7) + 2(4x² - 5x + 7) ← distribute both parenthesis
= 12x³ - 15x² + 21x + 8x² - 10x + 14 ← collect like terms
= 12x³ - 7x² + 11x + 14
(21 and 54): 3
(55 and 90): 5
(16 and 30): 2
(42 and 91): 7
(66 and 121): 11
I think its either A or B