Answer: B (-2)
Step-by-step explanation:
[log base b of a = c] turns into [b^c = a]
You have log base 5 of 1/25 = ?, so it turns into 5^? = 1/25
This part is sort of guess and check, but we can look at it to find the answer pretty easily. First, it's 1/n, so we should use a negative power: 5^-1 = 1/5
In addition to being in the denominator, it's 25, which is 5^2.
So, if we want to put it in a reciprocal as well as square it, we can use -2:
5^(-2) = 1/(5^2) = 1/25
Since -2 (B) is the exponent we place on 5 to get 1/25, it is also the answer to log base 5 of 1/25.
