document.write( "Question 119567: can you please explain this to me step by step so i can understand it.\r
\n" ); document.write( "\n" ); document.write( "log(3-2x) - log (x+9)=0\r
\n" ); document.write( "\n" ); document.write( "i hope you can help me understand this\r
\n" ); document.write( "\n" ); document.write( "thank you
\n" ); document.write( "julie
\n" ); document.write( "

Algebra.Com's Answer #87666 by MaxLiebling(13)\"\" \"About 
You can put this solution on YOUR website!
Start with the given equation:
\n" ); document.write( "\"log%28%283-2x%29%29+-+log%28%28x%2B9%29%29+=+0\"
\n" ); document.write( "add \"log%28%28x%2B9%29%29\" to both sides:
\n" ); document.write( "\"log%28%283-2x%29%29+=+log%28%28x%2B9%29%29\"
\n" ); document.write( "Note: logarithm is a strictly increasing function AND on both sides you have nothing but a Log(...) -> drop Log:
\n" ); document.write( "\"3-2x+=+x%2B9\"
\n" ); document.write( "add \"2x-9\" to both sides:
\n" ); document.write( "\"%283-2x%29+%2B+%282x-9%29+=+%28x%2B9%29+%2B+%282x-9%29\"
\n" ); document.write( "calculate left side:
\n" ); document.write( "\"%283-2x%29+%2B+%282x-9%29\" = \"3+%2B+%28-2x%2B2x%29-9%29\" = \"3+%2B+0+-9%29\" = \"-6%29\"
\n" ); document.write( "calculate right side:
\n" ); document.write( "\"%28x%2B9%29+%2B+%282x-9%29\" = \"%28x%2B2x%29+%2B+%289-9%29\" = \"%28x%2B2x%29+%2B+0\" = \"3x%29\"
\n" ); document.write( "combine both sides:
\n" ); document.write( "\"-6%29\" = \"3x%29\"
\n" ); document.write( "that is:
\n" ); document.write( "\"3x+=+-6%29\"
\n" ); document.write( "divide both sides by 3:
\n" ); document.write( "\"x+=+-6%2F3%29\"
\n" ); document.write( "calculate \"-6%2F3%29\" = \"-2%29\"
\n" ); document.write( "\"x+=+-2%29\"
\n" ); document.write( "proof left hand side:
\n" ); document.write( "\"log%28%283-2x%29%29\" = \"log%28%283-2%2A%28-2%29%29%29\" = \"log%28%283-%282%2A%28-2%29%29%29%29\" = \"log%28%283-%28-4%29%29%29\" = \"log%28%283%2B4%29%29\" = \"log%28%287%29%29\"
\n" ); document.write( "proof right hand side:
\n" ); document.write( "\"log%28%28x%2B9%29%29\" = \"log%28%28%28-2%29%2B9%29%29\" = \"log%28%28-2%2B9%29%29\" = \"log%28%287%29%29\"
\n" ); document.write( "both sides are equal: \"log%28%287%29%29\"
\n" ); document.write( "
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