document.write( "Question 374764: Please solve each system\r
\n" ); document.write( "\n" ); document.write( "-8x - 7y =2
\n" ); document.write( "7x + 6y = -1
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Algebra.Com's Answer #266507 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-7y=2%2C7x%2B6y=-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"6%28-8x-7y%29=6%282%29\" Multiply the both sides of the first equation by 6.\r
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\n" ); document.write( "\n" ); document.write( "\"-48x-42y=12\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"7%287x%2B6y%29=7%28-1%29\" Multiply the both sides of the second equation by 7.\r
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\n" ); document.write( "\n" ); document.write( "\"49x%2B42y=-7\" 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%28-48x-42y=12%2C49x%2B42y=-7%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( "\"%28-48x-42y%29%2B%2849x%2B42y%29=%2812%29%2B%28-7%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-48x%2B49x%29%2B%28-42y%2B42y%29=12%2B-7\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B0y=5\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x=5\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"-48x-42y=12\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-48%285%29-42y=12\" Plug in \"x=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"-240-42y=12\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-42y=12%2B240\" Add \"240\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-42y=252\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28252%29%2F%28-42%29\" Divide both sides by \"-42\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-6\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=5\" and \"y=-6\".\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-7y=2\" (red) and \"7x%2B6y=-1\" (green)
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