SOLUTION: SOLVE THE EQUATION In(x+5)-In(3)=In(x-3).

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Question 64825: SOLVE THE EQUATION In(x+5)-In(3)=In(x-3).
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
SOLVE THE EQUATION In(x+5)-In(3)=In(x-3).
ln%28x%2B5%29-ln%283%29-ln%28x-3%29=ln%28x-3%29-ln%28x-3%29
ln%28x%2B5%29-ln%283%29-ln%28x-3%29=0
ln%28%28x%2B5%29%2F%283%28x-3%29%29%29=0
%28x%2B5%29%2F%283%28x-3%29%29=e%5E0
%28x%2B5%29%2F%283x-9%29=1
%283x-9%29%28x%2B5%29%2F%283x-9%29=%283x-9%29%281%29
cross%28%283x-9%29%29%28x%2B5%29%2F%28cross%28%283x-9%29%29%29=3x-9
x%2B5=3x-9
x-x%2B5=3x-x-9
5=2x-9
5%2B9=2x-9%2B9
14=2x
14%2F2=2x%2F2
7=x
Check for extraneous solutions:
ln%287%2B5%29-ln%283%29=ln%287-3%29
ln%2812%29-ln%283%29=ln%284%29
ln%2812%2F3%29=ln%284%29
ln%284%29=ln%284%29 The solution x=7 is valid.
Happy Calculating!!!