document.write( "Question 405162: -4x+y=6
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Algebra.Com's Answer #286218 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system of equations:\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( "\"%28-4x%2By%29%2B%28-5x-y%29=%286%29%2B%2821%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-4x-5x%29%2B%28y-y%29=6%2B21\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x%2B0y=27\" Combine like terms. Notice how the y terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x=27\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2827%29%2F%28-9%29\" Divide both sides by \"-9\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2By=6\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4%28-3%29%2By=6\" Plug in \"x=-3\".\r
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\n" ); document.write( "\n" ); document.write( "\"12%2By=6\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"y=6-12\" Subtract \"12\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-6\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-3\" and \"y=-6\".\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 \"-4x%2By=6\" (red) and \"-5x-y=21\" (green) \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you\r
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