SOLUTION: Evaluate the following logarithms ,Solve for the following notations. Find xif log(x^2-21)=2

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Question 1022907: Evaluate the following logarithms ,Solve for the following notations.
Find xif log(x^2-21)=2
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x%5E2+-+21%29%29+=+2
<==> 10%5E2+=+x%5E2+-+21 ==> 121+=+x%5E2 ==> x = 11, -11.
Both are valid solutions.