document.write( "Question 550501: 9x + 11y = 86
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Algebra.Com's Answer #358809 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%289x%2B11y=86%2C9x-2y=-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-1%289x%2B11y%29=-1%2886%29\" Multiply the both sides of the first equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x-11y=-86\" 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%28-9x-11y=-86%2C9x-2y=-5%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( "\"%28-9x-11y%29%2B%289x-2y%29=%28-86%29%2B%28-5%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-9x%2B9x%29%2B%28-11y%2B-2y%29=-86%2B-5\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-13y=-91\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-13y=-91\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-91%29%2F%28-13%29\" Divide both sides by \"-13\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=7\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x-11y=-86\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x-11%287%29=-86\" Plug in \"y=7\".\r
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\n" ); document.write( "\n" ); document.write( "\"-9x-77=-86\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x=-86%2B77\" Add \"77\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-9x=-9\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-9%29%2F%28-9%29\" Divide both sides by \"-9\" 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( "So the solutions are \"x=1\" and \"y=7\".\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 \"9x%2B11y=86\" (red) and \"9x-2y=-5\" (green)
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