document.write( "Question 244763: Solve by using elimination method.\r
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\n" ); document.write( "\n" ); document.write( "separate problem:\r
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Algebra.Com's Answer #178964 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1\r
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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%28-4x-2y=3%2C2x%2By=1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%282x%2By%29=2%281%29\" Multiply the both sides of the second equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B2y=2\" 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%28-4x-2y=3%2C4x%2B2y=2%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( "\"%28-4x-2y%29%2B%284x%2B2y%29=%283%29%2B%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-4x%2B4x%29%2B%28-2y%2B2y%29=3%2B2\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B0y=5\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0=5\"Simplify.\r
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\n" ); document.write( "\n" ); document.write( "Since \"0=5\" is NEVER true, this means that there are no solutions. \r
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\n" ); document.write( "\n" ); document.write( "So the system is inconsistent.\r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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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%282x%2By=1%2C-x-y=-3%29\"\r
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\n" ); document.write( "\n" ); document.write( "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( "\"%282x%2By%29%2B%28-x-y%29=%281%29%2B%28-3%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282x-x%29%2B%28y-y%29=1-3\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B0y=-2\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2By=1\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28-2%29%2By=1\" Plug in \"x=-2\".\r
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\n" ); document.write( "\n" ); document.write( "\"-4%2By=1\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"y=1%2B4\" Add \"4\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=5\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-2\" and \"y=5\".\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 \"2x%2By=1\" (red) and \"-x-y=-3\" (green) \r
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