document.write( "Question 191774This question is from textbook saxon algebra 2
\n" ); document.write( ": logx+log(x+1)=log20
\n" ); document.write( "x=5
\n" ); document.write( "Am I correct?
\n" ); document.write( "

Algebra.Com's Answer #143899 by RAY100(1637)\"\" \"About 
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adding logs is multiply\r
\n" ); document.write( "\n" ); document.write( "x(x+1) = 20\r
\n" ); document.write( "\n" ); document.write( "x^2 +x -20 =0\r
\n" ); document.write( "\n" ); document.write( "(x+5) (x-4) =0\r
\n" ); document.write( "\n" ); document.write( "x= (-5), (+4) but we need to check\r
\n" ); document.write( "\n" ); document.write( "log(4) +log(4+1) = log 20\r
\n" ); document.write( "\n" ); document.write( ".602 +.699=1.30 ok therefore x=+4 is valid\r
\n" ); document.write( "\n" ); document.write( "however when we start log (-5) etc we find again that there are no logs for negative numbers
\n" ); document.write( "therefore x= (-5) is not valid
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