document.write( "Question 241749: solve each system of linear equations by using addition or elimination\r
\n" ); document.write( "\n" ); document.write( "8) 2x - y = -4
\n" ); document.write( " 4x + y = 1
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Algebra.Com's Answer #177054 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%282x-y=-4%2C4x%2By=1%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-y%29%2B%284x%2By%29=%28-4%29%2B%281%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282x%2B4x%29%2B%28-y%2By%29=-4%2B1\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B0y=-3\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"6x=-3\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-3%29%2F%286%29\" Divide both sides by \"6\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-1%2F2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"2x-y=-4\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28-1%2F2%29-y=-4\" Plug in \"x=-1%2F2\".\r
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\n" ); document.write( "\n" ); document.write( "\"-1-y=-4\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-4%2B1\" Add \"1\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-3\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-1%2F2\" and \"y=3\".\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.
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