Question

Logaritmo 6x+9=4
base 3

Answer 1

$\textbf{Dado:}\ \boxed{\mathrm{\log_b{a}=x\Longleftrightarrow b^x=a}}\\\\ \mathrm{log_3{(6x+9)}=4\Longleftrightarrow 3^4=6x+9}\\\\ \mathrm{81=6x+9\ \to\ 6x=81-9\ \to\ 6x=72}\\\\ \mathrm{x=\dfrac{72}{6}\ \to\ \boxed{\mathbf{x=12}}}$