document.write( "Question 186755: 2x+4y=12
\n" ); document.write( "x +y= 4 \r
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\n" ); document.write( "\n" ); document.write( "answer: (2,2)\r
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\n" ); document.write( "\n" ); document.write( "i need a full break down on how my text book got 2,2 as a solution
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Algebra.Com's Answer #139993 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%2B4y=12%2Cx%2By=4%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2%28x%2By%29=-2%284%29\" Multiply the both sides of the second equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x-2y=-8\" 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%2B4y=12%2C-2x-2y=-8%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%2B4y%29%2B%28-2x-2y%29=%2812%29%2B%28-8%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%282x%2B-2x%29%2B%284y%2B-2y%29=12%2B-8\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B2y=4\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2y=4\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%284%29%2F%282%29\" Divide both sides by \"2\" 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( "\"2x%2B4y=12\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B4%282%29=12\" Plug in \"y=2\".\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B8=12\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"2x=12-8\" Subtract \"8\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2x=4\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%284%29%2F%282%29\" Divide both sides by \"2\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=2\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=2\" 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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\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%2B4y=12\" (red) and \"x%2By=4\" (green)
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