SOLUTION: log3(x+12)+log3(x-12)=4

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Question 1051420: log3(x+12)+log3(x-12)=4
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
log3(x+12)+log3(x-12)=4
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If you mean log%283%2C%28x%2B12%29%29+%2B+log%283%2C%28x-12%29%29+=+4
log%283%2C%28x%2B12%29%2A%28x-12%29%29+=+4+=+log%283%2C3%5E4%29
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x^2 - 144 = 81
x^2 = 225
x = 15
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x = -15 is rejected since log(-15-12) is the log of a negative number.
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If you had mentioned that 3 was the base, someone might have done the problem sooner.