document.write( "Question 556865: 5x + 3y = -9
\n" ); document.write( "5x - 3y = -51 give the ordered pair as solution\r
\n" ); document.write( "\n" ); document.write( "I got an answer as -9/5 - -3/5y is this correct? \n" ); document.write( "

Algebra.Com's Answer #362293 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Sorry that's wrong.\r\n" );
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document.write( "I think you are trying to do it my substitution.  But the\r\n" );
document.write( "substitution method is best only when there is a term in x\r\n" );
document.write( "or y that has a coefficient of either 1 or -1.  This is not\r\n" );
document.write( "the case in this system.  So the best method here is the\r\n" );
document.write( "elimination method, sometimes called the addition method.\r\n" );
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document.write( "Add the equations just as they are and the y-terms will cancel:\r\n" );
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document.write( " 5x + 3y =  -9\r\n" );
document.write( " 5x - 3y = -51\r\n" );
document.write( "--------------\r\n" );
document.write( "10x      = -60\r\n" );
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document.write( "Divide both sides by 10\r\n" );
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document.write( "      = \r\n" );
document.write( "       x =  -6\r\n" );
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document.write( "Multiply the second equation by -1\r\n" );
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document.write( " 5x + 3y =  -9\r\n" );
document.write( "-5x + 3y =  51\r\n" );
document.write( "--------------\r\n" );
document.write( "  \r\n" );
document.write( "and add these term-by-term\r\n" );
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document.write( " 5x + 3y =  -9\r\n" );
document.write( "-5x + 3y =  51\r\n" );
document.write( "--------------\r\n" );
document.write( "      6y =  42\r\n" );
document.write( "       = \r\n" );
document.write( "       y = 7\r\n" );
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document.write( "Solution (x,y) = (-6,7)\r\n" );
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document.write( "Edwin

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