SOLUTION: log(x+20)+log(x)=2

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Question 1130087: log(x+20)+log(x)=2
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39630) About Me  (Show Source):
Answer by ikleyn(52908) About Me  (Show Source):
You can put this solution on YOUR website!
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The correct answer is  x= -10+%2B+10%2Asqrt%282%29.


Check.  x^2 + 20x = %28-10%2B10%2Asqrt%282%29%29%5E2+%2B+20%2A%28-10%2B10%2Asqrt%282%29%29 = 100+-+200%2Asqrt%282%29+%2B+200+%2B+-200+%2B+200%2Asqrt%282%29%29 = 100.   ! Correct !