Answer:
b = 28
Step-by-step explanation:
8*21 then 168/6 = 28
[tex] \frac{6}{8} = \frac{21}{b} \\ \\ b = \frac{21 \times 8}{6} \\ \\ b = \frac{7\times 8}{2} \\ \\ b = 7 \times 4 \\ \\ \huge \red{ \boxed{ b = 28}}[/tex]
