document.write( "Question 550713: -8x – 4y = -68
\n" ); document.write( " x + 3y = 16
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Algebra.Com's Answer #359013 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%28-8x-4y=-68%2Cx%2B3y=16%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"8%28x%2B3y%29=8%2816%29\" Multiply the both sides of the second equation by 8.\r
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\n" ); document.write( "\n" ); document.write( "\"8x%2B24y=128\" 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%28-8x-4y=-68%2C8x%2B24y=128%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( "\"%28-8x-4y%29%2B%288x%2B24y%29=%28-68%29%2B%28128%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-8x%2B8x%29%2B%28-4y%2B24y%29=-68%2B128\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B20y=60\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"20y=60\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2860%29%2F%2820%29\" Divide both sides by \"20\" 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( "\"-8x-4y=-68\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-8x-4%283%29=-68\" Plug in \"y=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"-8x-12=-68\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-8x=-68%2B12\" Add \"12\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-8x=-56\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-56%29%2F%28-8%29\" Divide both sides by \"-8\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=7\" Reduce.\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 \"-8x-4y=-68\" (red) and \"x%2B3y=16\" (green)
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