
Explanation:
To solve this logarithmic expression, we need to ask ourselves: what power of 5 gives us the fraction
? In other words, we need to solve the equation:

We can simplify
to
, so our equation becomes:

Now we may find
by applying the rule "if two powers with the same base are equal, then their exponents must be equal." As a result, we have:

So the value of the logarithmic expression
is -2.
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