Question 690977: Solve. include approximations to the nearest thousandth.
ln(x-6)+ln(x+5)=ln42
Answer by nerdybill(7384)   (Show Source):
You can put this solution on YOUR website!
ln(x-6)+ln(x+5)=ln42
ln[(x-6)(x+5)] = ln42
(x-6)(x+5) = 42
x^2+5x-6x-30 = 42
x^2-x-30 = 42
x^2-x-72 = 0
(x+8)(x-9) = 0
x = {-8, 9}
The negative solution is extraneous throw it out leaving:
x = 9
or, to the nearest thousandth:
x = 9.00
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