[tex]\log_ab=c\iff a^c=b\qquad(*)\\\\\log_ab^c=c\cdot\log_ab\qquad(**)\\\\---------------------\\\\\log_3x^6=12\qquad\text{use}\ (**)\\\\6\log_3x=12\qquad\text{divide both sides by 6}\\\\\log_3x=2\qquad\text{Use}\ (*)\\\\3^2=x\to\boxed{x=9}[/tex]
