document.write( "Question 264568: -4x+9y=9
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\n" ); document.write( "\n" ); document.write( "how do this problem by elimination?
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Algebra.Com's Answer #194763 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%28-4x%2B9y=9%2Cx-3y=-6%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x-3y%29=3%28-6%29\" Multiply the both sides of the second equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"3x-9y=-18\" 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%28-4x%2B9y=9%2C3x-9y=-18%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( "\"%28-4x%2B9y%29%2B%283x-9y%29=%289%29%2B%28-18%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-4x%2B3x%29%2B%289y%2B-9y%29=9%2B-18\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-x%2B0y=-9\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"-x=-9\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-9%29%2F%28-1%29\" Divide both sides by \"-1\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=9\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x%2B9y=9\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-4%289%29%2B9y=9\" Plug in \"x=9\".\r
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\n" ); document.write( "\n" ); document.write( "\"-36%2B9y=9\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"9y=9%2B36\" Add \"36\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"9y=45\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2845%29%2F%289%29\" Divide both sides by \"9\" 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( "So the solutions are \"x=9\" 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 \"-4x%2B9y=9\" (red) and \"x-3y=-6\" (green)
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