document.write( "Question 550476: HELLLLPPPP PLEASE....solve using subtraction method 7x + 6y = -5 and -7x + y = 40....type an ordered pair \n" ); document.write( "
Algebra.Com's Answer #358770 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%287x%2B6y=-5%2C-7x%2By=40%29\"\r
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\n" ); document.write( "\n" ); document.write( "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( "\"%287x%2B6y%29%2B%28-7x%2By%29=%28-5%29%2B%2840%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%287x%2B-7x%29%2B%286y%2B1y%29=-5%2B40\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B7y=35\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"7y=35\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2835%29%2F%287%29\" Divide both sides by \"7\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"7x%2B6y=-5\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"7x%2B6%285%29=-5\" Plug in \"y=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"7x%2B30=-5\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"7x=-5-30\" Subtract \"30\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"7x=-35\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-35%29%2F%287%29\" Divide both sides by \"7\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=-5\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-5\" and \"y=5\".\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=-5\" (red) and \"-7x%2By=40\" (green) \r
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\n" ); document.write( "\n" ); document.write( "So again, the answer is the ordered pair (-5, 5)
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