document.write( "Question 243528: Solve by the elimination method.\r
\n" ); document.write( "\n" ); document.write( "x+3y=14
\n" ); document.write( "-x+7y=6
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Algebra.Com's Answer #178400 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system of equations:\r
\n" ); document.write( "\n" ); document.write( "\"system%28x%2B3y=14%2C-x%2B7y=6%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( "\"%28x%2B3y%29%2B%28-x%2B7y%29=%2814%29%2B%286%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-x%29%2B%283y%2B7y%29=14%2B6\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B10y=20\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"10y=20\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2820%29%2F%2810%29\" Divide both sides by \"10\" 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( "\"x%2B3y=14\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3%282%29=14\" Plug in \"y=2\".\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B6=14\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"x=14-6\" Subtract \"6\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=8\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=8\" 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 \"x%2B3y=14\" (red) and \"-x%2B7y=6\" (green) \r
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