document.write( "Question 191971: using elimination method solve problem 3x-2y=-1 4x+y=6 \n" ); document.write( "
Algebra.Com's Answer #144036 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%283x-2y=-1%2C4x%2By=6%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%284x%2By%29=2%286%29\" Multiply the both sides of the second equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"8x%2B2y=12\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "So we have the new system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%283x-2y=-1%2C8x%2B2y=12%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:\r
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\n" ); document.write( "\n" ); document.write( "\"%283x-2y%29%2B%288x%2B2y%29=%28-1%29%2B%2812%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%2B8x%29%2B%28-2y%2B2y%29=-1%2B12\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"11x%2B0y=11\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"11x=11\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2811%29%2F%2811%29\" Divide both sides by \"11\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"3x-2y=-1\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%281%29-2y=-1\" Plug in \"x=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"3-2y=-1\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-1-3\" Subtract \"3\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-4\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4%29%2F%28-2%29\" Divide both sides by \"-2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=1\" and \"y=2\".\r
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\n" ); document.write( "\n" ); document.write( "Which form the ordered pair .\r
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\n" ); document.write( "\n" ); document.write( "This means that the system is consistent and independent.\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"3x-2y=-1\" (red) and \"4x%2By=6\" (green) \r
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