document.write( "Question 196630: How can you solve the following system of euqations for x?
\n" ); document.write( "2x+y=7
\n" ); document.write( "x-y=2
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Algebra.Com's Answer #147379 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( "\"%282x%2By%29%2B%28x-y%29=%287%29%2B%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282x%2Bx%29%2B%28y-y%29=7%2B2\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"3x%2B0y=9\" Combine like terms. Notice how the \"y\" terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"3x=9\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%289%29%2F%283%29\" Divide both sides by \"3\" 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( "\"2x%2By=7\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%283%29%2By=7\" Plug in \"x=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"6%2By=7\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"y=7-6\" Subtract \"6\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=1\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=3\" and \"y=1\".\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=7\" (red) and \"x-y=2\" (green) \r
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