Answer:
b is -6 or -10
Step-by-step explanation:
[tex] \frac{1}{b} = \frac{1}{b - 12} + \frac{ {b}^{2} + 16b + 48}{ {b}^{2} - 12b} \\ \\ \frac{1}{b} = \frac{b + ( {b}^{2} + 16b + 48)}{b(b - 12)} \\ \\ b - 12= b + ( {b}^{2} + 16b + 48) \\ {b}^{2} + 16b + 60= 0 \\ (b + 6)(b + 10) = 0 \\ b = - 6 \\ and \\ b = - 10[/tex]