document.write( "Question 146544: -7x+6y=59
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Algebra.Com's Answer #106987 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"-1%28-8x%2B6y%29=-1%2858%29\" Multiply the both sides of the second equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "\"8x-6y=-58\" 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%28-7x%2B6y=59%2C8x-6y=-58%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( "\"%28-7x%2B6y%29%2B%288x-6y%29=%2859%29%2B%28-58%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-7x%2B8x%29%2B%286y%2B-6y%29=59%2B-58\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B0y=1\" Combine like terms. Notice how the y terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"x=1\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"-7x%2B6y=59\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-7%281%29%2B6y=59\" Plug in \"x=1\".\r
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\n" ); document.write( "\n" ); document.write( "\"-7%2B6y=59\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"6y=59%2B7\" Add \"7\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"6y=66\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2866%29%2F%286%29\" Divide both sides by \"6\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=11\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So our answer is \"x=1\" and \"y=11\".\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 two equations are 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 \"-7x%2B6y=59\" (red) and \"-8x%2B6y=58\" (green) \r
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