Respuesta :

Hn, well you should use the rule to answer this.. [tex]log_a(n)-log_a(m)=log_a (\frac{n}{m} )[/tex]
Sorry if this doesn't seem to help, but here is the explanation: 
[tex]log_2 (\frac{12b-21}{b^2-3} )=2[/tex]
[tex] \frac{12b-21}{b^2-3} =4[/tex]
[tex]12b-21=4(b^4-3)[/tex]
[tex]0=4b^2-12b-12+21[/tex]
[tex]0=4b^2-12b+9 [/tex]
[tex]0=4b^2-6b-6b+9[/tex]
[tex]0=2b(2b-3)-3(2b-3)[/tex]
[tex]0=(2b-3)(2b-3)[/tex]
[tex]b= \frac{3}{2} [/tex]
Hn, so from this information we can determine that this solution does not work. And so forth your solution set shall indeed be: {x= 0}

I wish you good luck on your homework and hopefully I was somewhat beneficial to your needs. 

Best regards~ Sans