document.write( "Question 198232: If 5x-6y = -123 and 3x + 13y = -107, what is the value of x and y? \n" ); document.write( "
Algebra.Com's Answer #148689 by jim_thompson5910(35256)\"\" \"About 
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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%285x-6y=-123%2C3x%2B13y=-107%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%285x-6y%29=3%28-123%29\" Multiply the both sides of the first equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"15x-18y=-369\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-5%283x%2B13y%29=-5%28-107%29\" Multiply the both sides of the second equation by -5.\r
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\n" ); document.write( "\n" ); document.write( "\"-15x-65y=535\" 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%2815x-18y=-369%2C-15x-65y=535%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( "\"%2815x-18y%29%2B%28-15x-65y%29=%28-369%29%2B%28535%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2815x%2B-15x%29%2B%28-18y%2B-65y%29=-369%2B535\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-83y=166\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-83y=166\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28166%29%2F%28-83%29\" Divide both sides by \"-83\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"15x-18y=-369\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"15x-18%28-2%29=-369\" Plug in \"y=-2\".\r
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\n" ); document.write( "\n" ); document.write( "\"15x%2B36=-369\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"15x=-369-36\" Subtract \"36\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"15x=-405\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-405%29%2F%2815%29\" Divide both sides by \"15\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-27\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-27\" and \"y=-2\".\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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