document.write( "Question 166125: I am needing to solve this equation by the addition (elimination method)
\n" ); document.write( "2x+4y=8
\n" ); document.write( "7x+2y=10
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Algebra.Com's Answer #122416 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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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%2B4y=8%2C7x%2B2y=10%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2%287x%2B2y%29=-2%2810%29\" Multiply the both sides of the second equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-14x-4y=-20\" 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%282x%2B4y=8%2C-14x-4y=-20%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( "\"%282x%2B4y%29%2B%28-14x-4y%29=%288%29%2B%28-20%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282x%2B-14x%29%2B%284y%2B-4y%29=8%2B-20\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-12x%2B0y=-12\" Combine like terms. Notice how the y terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-12x=-12\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-12%29%2F%28-12%29\" Divide both sides by \"-12\" 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( "\"2x%2B4y=8\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%281%29%2B4y=8\" Plug in \"x=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"2%2B4y=8\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"4y=8-2\" Subtract \"2\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"4y=6\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%286%29%2F%284%29\" Divide both sides by \"4\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%2F2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=1\" and \"y=3%2F2\".\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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