document.write( "Question 968826: How do you solve logx+log(x-21)=2 \n" ); document.write( "

Algebra.Com's Answer #591984 by rothauserc(4718) $\"\"$ $\"About$

You can put this solution on YOUR website!
logx +log(x-21) = 2
\n" ); document.write( "use log rule log(xy) = log(x) + log(y)
\n" ); document.write( "log (x^2 -21x) = 2
\n" ); document.write( "use definition of log
\n" ); document.write( "x^2 -21x = 10^2
\n" ); document.write( "x^2 -21x -100 = 0
\n" ); document.write( "factor equation
\n" ); document.write( "(x-25)*(x+4) = 0
\n" ); document.write( "x = 25 or -4
\n" ); document.write( " \n" ); document.write( "

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