SOLUTION: log (x+4) + log (x)=9

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Question 923990: log (x+4) + log (x)=9
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x%2B4%29%29+%2B+log%28x%29=9
Combining into one log...


log%28%28%28x%2B4%29%28x%29%29%29=9

raise 10 to both sides of the equation...
x%5E2%2B4%2Ax=10%5E9

x%5E2%2B4%2Ax-1000000000=0
After solving we note that only positive numbers are solutions (Why?)

x%5B1%5D=-2+%2B+82%2A+sqrt%28148721%29