SOLUTION: find solution 1n(x^2+3x)-1n 10=0

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Question 319538: find solution 1n(x^2+3x)-1n 10=0
Found 2 solutions by nerdybill, stanbon:
Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website!
1n(x^2+3x)-1n 10=0
.
ln(x^2+3x)/10 =0
(x^2+3x)/10 = e^0
(x^2+3x)/10 = 1
x^2+3x = 10
x^2+3x-10 = 0
(x+5)(x-2) = 0
x = {-5, 2}

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
find solution 1n(x^2+3x)-1n 10=0
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ln[(x^2+3x)/10] = 0
(x^2+3x)/10 = e^0 = 1
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x^2 + 2x = 10
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x^2 + 2x-10 = 0
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(x+5)(x-3) = 0
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x = -5 or x = 3
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Check:
x = -5 ??
ln(25-15)-ln(10) = 0
true
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x = 3 ??
ln(9+9) - ln(10) = 0
false
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Final Answer: x = -5
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Cheers,
Stan H.