document.write( "Question 169709This question is from textbook elementary and Intermediate algebra concepts and application
\n" ); document.write( ": Explain how to apply elimination in solving a system of equations.
\n" ); document.write( "a. Explain how to apply substitution in solving a system of equations.
\n" ); document.write( "b. Demonstrate each technique in solving the system
\n" ); document.write( "3x + 9y = 12
\n" ); document.write( "5x - 4y = 3
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Algebra.Com's Answer #125245 by Edwin McCravy(20060) $\"\"$ $\"About$

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Explain how to apply elimination in solving a system of equations.
\n" ); document.write( "a. Explain how to apply substitution in solving a system of equations.
\n" ); document.write( "b. Demonstrate each technique in solving the system\r
\n" ); document.write( "\n" ); document.write( " $\"system%283x+%2B+9y+=+12%2C5x+-+4y+=+3%29\"$ \r
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document.write( "By elimination:\r\n" );
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document.write( "First eliminate  and find .\r\n" );
document.write( "Multiply the first equation through by  \r\n" );
document.write( "and the second equation through by :\r\n" );
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document.write( "Now add vertically term by term:\r\n" );
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document.write( "Divide both sides by \r\n" );
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document.write( "----\r\n" );
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document.write( "Next eliminate  and find .\r\n" );
document.write( "Multiply the first equation through by \r\n" );
document.write( " and the second equation through \r\n" );
document.write( "by :\r\n" );
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document.write( "Now add vertically term by term:\r\n" );
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document.write( "Divide both sides by \r\n" );
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document.write( "Solution:   \r\n" );
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document.write( "Now do the same problem from scratch using\r\n" );
document.write( "substitution:\r\n" );
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document.write( "Solve the first equation for :\r\n" );
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document.write( "Add  to both sides:\r\n" );
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document.write( "Divide through every term by 3:\r\n" );
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document.write( "Simplify:\r\n" );
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document.write( "Substitute  for \r\n" );
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document.write( "Distribute:\r\n" );
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document.write( "Add  to both sides:\r\n" );
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document.write( "Divide both sides by \r\n" );
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document.write( "Now substitute  for \r\n" );
document.write( "in\r\n" );
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document.write( "Write the  as  and \r\n" );
document.write( "write the  as \r\n" );
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document.write( "The LCD is \r\n" );
document.write( "Multiply the  by \r\n" );
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document.write( "Solution:  \r\n" );
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document.write( "Edwin

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