bearing in mind that for the "change of base" rule, it doesn't matter what base one uses, so long is the same atop and below.
[tex]\bf \textit{Logarithm Change of Base Rule}
\\\\
log_a b\implies \cfrac{log_c b}{log_c a}
\\\\\\
\textit{Logarithm Cancellation Rules}
\\\\ \boxed{log_a a^x = x}\qquad \qquad a^{log_a x=x}\\\\
-------------------------------\\\\
log_{25}(125)\implies \cfrac{log_5(125)}{log_5(25)}\qquad
\begin{cases}
125=5^3\\
25=5^2
\end{cases}\implies \cfrac{log_5(5^3)}{log_5(5^2)}
\implies
\cfrac{3}{2}[/tex]