document.write( "Question 236841: -x+2y=16
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Algebra.Com's Answer #174235 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%28-x%2B2y=16%2Cx-3y=-21%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( "\"%28-1x%2B2y%29%2B%28x-3y%29=%2816%29%2B%28-21%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-1x%2B1x%29%2B%282y%2B-3y%29=16%2B-21\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-y=-5\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-y=-5\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-5%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=5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-1x%2B2y=16\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-1x%2B2%285%29=16\" Plug in \"y=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"-1x%2B10=16\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=16-10\" Subtract \"10\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=6\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%286%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-6\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-6\" and \"y=5\".\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%2B2y=16\" (red) and \"x-3y=-21\" (green) \r
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