SOLUTION: What is... Ln x+ ln (x+7)=0 And please show me the steps and how you arrived to the answer. Thank You!!!

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Question 806444: What is...
Ln x+ ln (x+7)=0
And please show me the steps and how you arrived to the answer. Thank
You!!!
Found 2 solutions by Alan3354, josmiceli:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
What is...
Ln x+ ln (x+7)=0
===================
It's an equation.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+ln%28x%29+%2B+ln%28+x%2B7+%29+=+0+
+ln%28x%29+=+-ln%28+x%2B7+%29+
+ln%28x%29+=+ln%28+1%2F%28x%2B7%29+%29+
+x+=+1%2F%28x%2B7%29+
+x%2A%28+x%2B7+%29+=+1+
+x%5E2+%2B+7x+=+1+
+x%5E2+%2B+7x+%2B+%287%2F2%29%5E2+=+1+%2B+%287%2F2%29%5E2+
+x%5E2+%2B+7x+%2B+49%2F4+=+4%2F4+%2B+49%2F4+
+x%5E2+%2B+7x+%2B+49%2F4+=+53%2F4+
+%28+x+%2B+7%2F2+%29%5E2+=+53%2F4+
+x+%2B+7%2F2+=+sqrt%2853%29%2F2+
+x+=+%28+-7+%2B+sqrt%2853%29%29%2F2+ answer
and
+x+=+%28+-7+-+sqrt%2853%29%29%2F2+ is not allowed because a
positive base raised to a power cannot result in
a negative number.
--------------------
check answer:
+ln%28x%29+%2B+ln%28+x%2B7+%29+=+0+
+x+=+%28+-7+%2B+sqrt%2853%29%29%2F2+
+x+=+%28+-7+%2B+7.28+%29%2F2+
+x+=+.28%2F2+
+x+=+.14+
+ln%28.14%29+%2B+ln%28+.14%2B7+%29+=+0+
+-1.966+%2B+1.966+=+0+
Looks OK