SOLUTION: How do I solve the following to THREE decimal places? ln x + ln(x+7) = -5

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Question 366461: How do I solve the following to THREE decimal places?
ln x + ln(x+7) = -5
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
ln+x+%2B+ln%28x%2B7%29+=+-5
ln%28x%28x%2B7%29%29+=+ln%28x%5E2%2B7x%29+=+-5,
Hence+x%5E2%2B7x+=+e%5E-5, or+x%5E2%2B7x+-+e%5E-5+=+0 . Using the quadratic formula:
. The values are, to 3 decimal places, 0.001 (from 0.000962432), or -7.0001 (from -7.000962432). We have to eliminate the 2nd value, because it won't satisfy the original equation. The answer is 0.001.