Answer :

[tex]\frac{3b}{b + 2} + 12 = \frac{3b}{b + 2} + \frac{12(b + 2)}{1(b + 2)} = \frac{3b}{b + 2} + \frac{12b + 24}{b + 2} = \frac{15b + 24}{b + 2} = \frac{3(5b + 8)}{b + 2}[/tex]