document.write( "Question 153100: 3x-2y=4
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Algebra.Com's Answer #112579 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%283x-2y=4%2C2x-5y=21%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2%283x-2y%29=-2%284%29\" Multiply the both sides of the first equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x%2B4y=-8\" Distribute and multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"3%282x-5y%29=3%2821%29\" Multiply the both sides of the second equation by 3.\r
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\n" ); document.write( "\n" ); document.write( "\"6x-15y=63\" 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%28-6x%2B4y=-8%2C6x-15y=63%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( "\"%28-6x%2B4y%29%2B%286x-15y%29=%28-8%29%2B%2863%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-6x%2B6x%29%2B%284y%2B-15y%29=-8%2B63\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B-11y=55\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"-11y=55\" Simplify.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2855%29%2F%28-11%29\" Divide both sides by \"-11\" 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( "\"-6x%2B4y=-8\" Now go back to the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x%2B4%28-5%29=-8\" Plug in \"y=-5\".\r
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\n" ); document.write( "\n" ); document.write( "\"-6x-20=-8\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x=-8%2B20\" Add \"20\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-6x=12\" Combine like terms on the right side.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2812%29%2F%28-6%29\" Divide both sides by \"-6\" 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 our answer is \"x=-2\" 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 \"3x-2y=4\" (red) and \"2x-5y=21\" (green) \r
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