document.write( "Question 148094This question is from textbook
\n" ); document.write( ": i need step by step solution using elimination\r
\n" ); document.write( "\n" ); document.write( "x+y=-12
\n" ); document.write( "x-y=-4
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Algebra.Com's Answer #108487 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=-12%2Cx-y=-4%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%28x-y%29=%28-12%29%2B%28-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2Bx%29%2B%28y-y%29=-12%2B-4\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B0y=-16\" Combine like terms. Notice how the y terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"2x=-16\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-16%29%2F%282%29\" Divide both sides by \"2\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-8\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By=-12\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-8%2By=-12\" Plug in \"x=-8\".\r
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\n" ); document.write( "\n" ); document.write( "\"-8%2By=-12\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-12%2B8\" Add \"8\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-4\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=-8\" and \"y=-4\".\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=-12\" (red) and \"x-y=-4\" (green)
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