document.write( "Question 319710: 2x-4y=6 and 4x+y=21 work addition method and is it independent, inconsistent or dependent. \n" ); document.write( "
Algebra.Com's Answer #228964 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%282x-4y=6%2C4x%2By=21%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%284x%2By%29=4%2821%29\" Multiply the both sides of the second equation by 4.\r
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\n" ); document.write( "\n" ); document.write( "\"16x%2B4y=84\" 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%282x-4y=6%2C16x%2B4y=84%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( "\"%282x-4y%29%2B%2816x%2B4y%29=%286%29%2B%2884%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282x%2B16x%29%2B%28-4y%2B4y%29=6%2B84\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"18x%2B0y=90\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"18x=90\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2890%29%2F%2818%29\" Divide both sides by \"18\" 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( "\"2x-4y=6\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%285%29-4y=6\" Plug in \"x=5\".\r
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\n" ); document.write( "\n" ); document.write( "\"10-4y=6\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=6-10\" Subtract \"10\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-4y=-4\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4%29%2F%28-4%29\" Divide both sides by \"-4\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=1\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=5\" and \"y=1\".\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 \"2x-4y=6\" (red) and \"4x%2By=21\" (green) \r
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