Answer
$\log_5{\frac{1}{125}}=-3$
Work Step by Step
RECALL:
$b^y=x \longleftrightarrow \log_b{x} =y .$
Use the definition above to obtain
$5^{-3} = \frac{1}{125} \longrightarrow \log_5{\frac{1}{125}}=-3.$
Thus, the equivalent logarithmic form of the given expression is
$\log_5{\frac{1}{125}}=-3.$
