SOLUTION: Solve the equation for x: 2log base 5 of x + log base 5 of 3 = log base 5(1/125)

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Question 455264: Solve the equation for x: 2log base 5 of x + log base 5 of 3 = log base 5(1/125)
Found 2 solutions by lwsshak3, MathTherapy:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation for x: 2log base 5 of x + log base 5 of 3 = log base 5(1/125)
..
2log5(x)+log5(3)=log5(1/125)=log5(5^-3)=-3 (log of the base^x = x)
log5(3x^2) (exponent and multiplication rules)
Convert to exponential form: (base(5) raised to log of number(-3)=number(3x^2)
5^-3=3x^2
x^2=1/125*3
x=1/(5√5*√3)=1/(5√15)
x=√15/75

Answer by MathTherapy(10719) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation for x: 2log base 5 of x + log base 5 of 3 = log base 5(1/125)

The other person's answer, x+=+sqrt%2815%2F75%29 is WRONG!!

2%2Alog+%285%2C+%28x%29%29+%2B+log+%285%2C+%283%29%29+=+log+%285%2C+%281%2F125%29%29, with x > 0
log+%285%2C+%28x%5E2%29%29+%2B+log+%285%2C+%283%29%29+=+log+%285%2C+%281%2F125%29%29
       log+%285%2C+%283x%5E2%29%29+=+log+%285%2C+%281%2F125%29%29
             3x%5E2+=+1%2F125
              x%5E2+=+%281%2F125%29%2F3
              x%5E2+=+%281%2F125%29+%2A+%281%2F3%29
              x%5E2+=+1%2F375
             highlight_green%28highlight%28highlight_green%28x+=+sqrt%281%2F375%29%29%29%29       OR      x+=+-sqrt%281%2F375%29 <==== IGNORE


             highlight_green%28highlight%28highlight_green%28x+=+sqrt%281%2F375%29%29%29%29 is an ACCEPTED solution, while highlight%28x+=+-sqrt%281%2F375%29%29 is NOT, because the LATTER is NOT > 0,
                         but the FORMER is (see constraint above).