You can put this solution on YOUR website! ln(x) + ln(x+5)=ln(x^3 + 15x)-ln(x)
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Adding logs is multiply and subtraction is divide, so we can write this
ln(x(x+5)) = ln((x^3+15x)/x)
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cancel out x on the right:
ln(x^2+5x) = ln(x^2 + 15)
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get rid of the ln's it's the same as:
x^2 + 5x = x^2 + 15
x^2 - x^2 + 5x = 15
x = 15/5
x = 3
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You can check this on your calc, replace x with 3 in the original problem