document.write( "Question 1004909: log3(2x-3)-log3(x+2)=3\r
\n" ); document.write( "\n" ); document.write( "PLEASE HELP!
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Algebra.Com's Answer #621263 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
Logarithm of a quotient is the difference of the logarithms, so
\n" ); document.write( "\"log%283%2C2x-3%29-log%283%2Cx%2B2%29=red%283%29\"--->\"log%283%2C%282x-3%29%2F%28x%2B2%29%29=red%283%29\"
\n" ); document.write( "Logarithm of something is the exponent you have to apply the base to get that something, so if there is a solution,
\n" ); document.write( "\"log%283%2C%282x-3%29%2F%28x%2B2%29%29=red%283%29\"--->\"%282x-3%29%2F%28x%2B2%29=3%5Ered%283%29\"--->\"%282x-3%29%2F%28x%2B2%29=27\" .
\n" ); document.write( "The rest is simple algebra:
\n" ); document.write( "\"%282x-3%29%2F%28x%2B2%29=27\"--->\"%282x-3%29=27%28x%2B2%29\"--->\"2x-3=27x%2B54\"--->\"2x-27x=54%2B3\"--->\"-25x=57\"--->\"x=57%2F%28-25%29\"--->\"x=-57%2F25=-%0D%0A2.28\"
\n" ); document.write( "The problem is that with \"x=-2.28\" , \"system%282x-3=-7.56%2Cx%2B2=-0.28%29\" ,
\n" ); document.write( "and logarithm of a negative number is undefined.
\n" ); document.write( "So, there are \"highlight%28no%29\"\"highlight%28solutions%29\" .
\n" ); document.write( "We could have started with \"there are no solutions with
\n" ); document.write( "\"system%282x-3%3C=0%2C%22or%22%2Cx%2B2%3C=0%29\"<--->\"system%28x%3C=3%2F2%2C%22or%22%2Cx%3C=-3%29\"<--->\"x%3C=3%2F2\" \".
\n" ); document.write( "For \"x%3E3%2F2\" both logarithms exist, and \"log%283%2C2x-3%29-log%283%2Cx%2B2%29=log%283%2C%282x-3%29%2F%28x%2B2%29%29\" .
\n" ); document.write( "Then, if you were in calculus class (and even if you weren't),
\n" ); document.write( "you would realize that in the domain of that function
\n" ); document.write( "\"%282x-3%29%2F%28x%2B2%29\" increases with \"x\" , and
\n" ); document.write( "\"log%283%2C%282x-3%29%2F%28x%2B2%29%29\" increases with \"%282x-3%29%2F%28x%2B2%29\" , so
\n" ); document.write( "\"log%283%2C%282x-3%29%2F%28x%2B2%29%29\" increases with \"x\" , and
\n" ); document.write( " ,
\n" ); document.write( "so \"log%283%2C%282x-3%29%2F%28x%2B2%29%29%3Clog%283%2C2%29%3C3\" .
\n" ); document.write( "Graphing \"log%283%2C%282x-3%29%2F%28x%2B2%29%29\" and \"log%283%2C2%29\" we get
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