SOLUTION: Evaluate the logarithm: log9 1/81

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Question 271046: Evaluate the logarithm:
log9 1/81

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Evaluate:
Log%5B9%5D%281%2F81%29+=+x Rewrite in exponential form:
9%5Ex+=+1%2F81 Substitute 1%2F81+=+1%2F9%5E2 = 9%5E%28-2%29
9%5Ex+=+9%5E%28-2%29 The bases are equal so the exponents are equal.
highlight%28x+=+-2%29