### Home > CCA2 > Chapter 6 > Lesson 6.2.2 > Problem6-115

6-115.

Use the definition of a logarithm to change $\log_27$ into a logarithmic expression of base 5.

$\log_27=x\\2^x=7$
$\log_5(2^x)=\log_57$
$x(\log_52)=\log_57$
$\log_{2}7 =\frac{\log_{5}7}{\log_{5}2}$