document.write( "Question 218279: give the corrdinates of intersection of the linear equations\r
\n" ); document.write( "\n" ); document.write( "2x+y= -4
\n" ); document.write( "4x+2y=-8
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Algebra.Com's Answer #164465 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%2By=-4%2C4x%2B2y=-8%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2%282x%2By%29=-2%28-4%29\" Multiply the both sides of the first equation by -2.\r
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\n" ); document.write( "\n" ); document.write( "\"-4x-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%28-4x-2y=8%2C4x%2B2y=-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( "\"%28-4x-2y%29%2B%284x%2B2y%29=%288%29%2B%28-8%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28-4x%2B4x%29%2B%28-2y%2B2y%29=8%2B-8\" Group like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"0x%2B0y=0\" Combine like terms. Notice how the x terms cancel out.\r
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\n" ); document.write( "\n" ); document.write( "\"0=0\"Simplify.\r
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\n" ); document.write( "\n" ); document.write( "Since \"0=0\" is always true, this means that there are an infinite number of solutions. \r
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\n" ); document.write( "\n" ); document.write( "So the system is consistent and dependent.\r
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\n" ); document.write( "\n" ); document.write( "Visually, this means that one graph is right on top of the other.
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