document.write( "Question 188203: 2r+3s=9
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Algebra.Com's Answer #141067 by Edwin McCravy(20060) $\"\"$ $\"About$
You can put this solution on YOUR website!
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document.write( "Eliminate r:\r\n" );
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document.write( "Notice that the coefficients of r are 2 and 3.\r\n" );
document.write( "Their common multiple is 6.  We can cause the\r\n" );
document.write( "r-terms to cancel if we multiply the first\r\n" );
document.write( "equation through by (-3), and the second one\r\n" );
document.write( "through by (+2)\r\n" );
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document.write( "Then you see that the coefficients of r are equal\r\n" );
document.write( "in magnitude but opposite in sign, so the will\r\n" );
document.write( "cance when we add those equations term by term.\r\n" );
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document.write( "---------------\r\n" );
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document.write( "Now we add straight down and the r terms cancel out\r\n" );
document.write( "and we add the other terms\r\n" );
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document.write( "Now in a lot of cases we switch over to substitution,\r\n" );
document.write( "but since  is not an integers, it is better\r\n" );
document.write( "to start all over and eliminate the other letter\r\n" );
document.write( "instead.\r\n" );
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document.write( "Eliminate s:\r\n" );
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document.write( "Notice that the coefficients of s are 3 and 2.\r\n" );
document.write( "Their common multiple is 6.  We can cause the\r\n" );
document.write( "s-terms to cancel if we multiply the first\r\n" );
document.write( "equation through by (-2), and the second one\r\n" );
document.write( "through by (+3)\r\n" );
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document.write( "Then you see that the coefficients of r are equal\r\n" );
document.write( "in magnitude but opposite in sign, so the will\r\n" );
document.write( "cance when we add those equations term by term.\r\n" );
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document.write( "\r\n" );
document.write( "---------------\r\n" );
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document.write( "Now we add straight down and the s terms cancel out\r\n" );
document.write( "and we add the other terms\r\n" );
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document.write( "---------------\r\n" );
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document.write( "Edwin
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