document.write( "Question 318610: 14x - 2y = 78
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Algebra.Com's Answer #228079 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%2814x-2y=78%2C2x-2y=6%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-1%282x-2y%29=-1%286%29\" Multiply the both sides of the second equation by -1.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%2B2y=-6\" 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%2814x-2y=78%2C-2x%2B2y=-6%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( "\"%2814x-2y%29%2B%28-2x%2B2y%29=%2878%29%2B%28-6%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2814x%2B-2x%29%2B%28-2y%2B2y%29=78%2B-6\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B0y=72\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=72\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2872%29%2F%2812%29\" Divide both sides by \"12\" to isolate \"x\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=6\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"14x-2y=78\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"14%286%29-2y=78\" Plug in \"x=6\".\r
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\n" ); document.write( "\n" ); document.write( "\"84-2y=78\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=78-84\" Subtract \"84\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-2y=-6\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-6%29%2F%28-2%29\" Divide both sides by \"-2\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=3\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=6\" and \"y=3\".\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 \"14x-2y=78\" (red) and \"2x-2y=6\" (green)
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