Question 153275: solve for x:
log5x(x-1)=2
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! solve for x:
log5x(x-1)=2
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This says "when the exponent of 10 is 2 then 10^2 = 5x(x-1)"
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EQUATION:
5x(x-1) = 10^2
5x^2 - 5x - 100 = 0
x^2 -x -20 = 0
(x-5)(x+4) = 0
x = 5 or x= -4
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Checking in the original problem:
Can x = 5 ?
log[5*5(5-1) = 2
log[100] = 2
true
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Can x = -4
log5(-4)(-4-1) = 2
log(100) = 2
true
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Cheers,
Stan H.
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