document.write( "Question 678365: -7x+6y=-11
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Algebra.Com's Answer #421326 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%28-7x%2B6y=-11%2C-5x-4y=17%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28-7x%2B6y%29=2%28-11%29\" Multiply the both sides of the first equation by 2.\r
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\n" ); document.write( "\n" ); document.write( "\"-14x%2B12y=-22\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28-5x-4y%29=3%2817%29\" Multiply the both sides of the second equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"-15x-12y=51\" 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%28-14x%2B12y=-22%2C-15x-12y=51%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( "\"%28-14x%2B12y%29%2B%28-15x-12y%29=%28-22%29%2B%2851%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-14x%2B-15x%29%2B%2812y%2B-12y%29=-22%2B51\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-29x%2B0y=29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-29x=29\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2829%29%2F%28-29%29\" Divide both sides by \"-29\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-14x%2B12y=-22\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-14%28-1%29%2B12y=-22\" Plug in \"x=-1\".\r
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\n" ); document.write( "\n" ); document.write( "\"14%2B12y=-22\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"12y=-22-14\" Subtract \"14\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"12y=-36\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-36%29%2F%2812%29\" Divide both sides by \"12\" 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( "So the solutions are \"x=-1\" 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 \"-7x%2B6y=-11\" (red) and \"-5x-4y=17\" (green)
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