Answer:
(3x+7)(x+3)
Step-by-step explanation:
Factors 3x^2+16x+21
3x^2+16x+21
=(3x+7)(x+3)
[tex]3 {x}^{2} + 16x + 21 \\ 3 {x}^{2} + 9x + 7x + 21 \\ 3x(x + 3) + 7(x + 3) \\ = (3x + 7)(x + 3)[/tex]
