SOLUTION: log x + log y (x-21)=2

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Question 528521: log x + log y (x-21)=2
Answer by lwsshak3(6505) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x
log x + log y (x-21)=2
log[x(x-21)]=2
convert to exponential form: base(10) raised to log of number(2)=number(x(x-21))
10^2=x^2-21x
x^2-21x-100=0
(x-25)(x+4)=0
x=25
or
x=-4