document.write( "Question 548770: I am not sure how to solve this system\r
\n" ); document.write( "\n" ); document.write( "x + y = -4
\n" ); document.write( "-x-5y=-8
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Algebra.Com's Answer #357202 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%2By=-4%2C-x-5y=-8%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%2By%29%2B%28-x-5y%29=%28-4%29%2B%28-8%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-x%29%2B%28y-5y%29=-4%2B-8\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x-4y=-12\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=-12\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-12%29%2F%28-4%29\" Divide both sides by \"-4\" 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( "\"x%2By=-4\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3=-4\" Plug in \"y=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-4-3\" Subtract \"3\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-7\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-7\" 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.\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%2By=-4\" (red) and \"-x-5y=-8\" (green) \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you\r
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\n" ); document.write( "\n" ); document.write( "Jim\r
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