document.write( "Question 1111531: log(x) + log(x − 48) = 2 \n" ); document.write( "

Algebra.Com's Answer #726535 by ikleyn(52795) $\"\"$ $\"About$

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document.write( "log(x) + log(x - 48) = 2  ====>\r\n" );
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document.write( "x*(x-48) = 100\r\n" );
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document.write( "x^2 - 48x - 100 = 0\r\n" );
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document.write( "(x-50)*(x+2) = 0  ====>\r\n" );
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document.write( "The last equation has the roots  x= 50  and  x= -2.\r\n" );
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document.write( "But since  x  and  (x-48)  must be positive under the logarithm,  only one root survives:  x= 50.\r\n" );
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document.write( "Answer.  x = 50.\r\n" );
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\n" ); document.write( "On logarithms and their properties, see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - WHAT IS the logarithm \r
\n" ); document.write( "\n" ); document.write( "    - Properties of the logarithm \r
\n" ); document.write( "\n" ); document.write( "    - Change of Base Formula for logarithms \r
\n" ); document.write( "\n" ); document.write( "    - Solving logarithmic equations \r
\n" ); document.write( "\n" ); document.write( "    - Using logarithms to solve real world problems \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Logarithms\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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