document.write( "Question 179497: 4x + 5y =40
\n" ); document.write( "6x + 7y =58\r
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\n" ); document.write( "\n" ); document.write( "the same variable will satifty the solution
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Algebra.Com's Answer #134440 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%284x%2B5y=40%2C6x%2B7y=58%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%284x%2B5y%29=3%2840%29\" Multiply the both sides of the first equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B15y=120\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-2%286x%2B7y%29=-2%2858%29\" Multiply the both sides of the second equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-12x-14y=-116\" 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%2812x%2B15y=120%2C-12x-14y=-116%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( "\"%2812x%2B15y%29%2B%28-12x-14y%29=%28120%29%2B%28-116%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%2812x%2B-12x%29%2B%2815y%2B-14y%29=120%2B-116\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2By=4\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"y=4\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B15y=120\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B15%284%29=120\" Plug in \"y=4\".\r
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\n" ); document.write( "\n" ); document.write( "\"12x%2B60=120\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=120-60\" Subtract \"60\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"12x=60\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2860%29%2F%2812%29\" Divide both sides by \"12\" 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( "So our answer is \"x=5\" and \"y=4\".\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%2B5y=40\" (red) and \"6x%2B7y=58\" (green) \r
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