document.write( "Question 146408: Solve the system of equations by graphing. Then classify the system as consistent or inconsistent or inconsistent and the equations as dependent or independent.
\n" ); document.write( "2x-6y=42
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Algebra.Com's Answer #106886 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
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\n" ); document.write( "\n" ); document.write( "\"2x-6y=42\"\r
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\n" ); document.write( "\n" ); document.write( "In order to graph these equations, we need to solve for y for each equation.\r
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\n" ); document.write( "\n" ); document.write( "So let's solve for y on the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"2x-6y=42\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"-6y=42-2x\" Subtract \"2+x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-6y=-2x%2B42\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2x%2B42%29%2F%28-6%29\" Divide both sides by \"-6\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2%2F-6%29x%2B%2842%29%2F%28-6%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F3%29x-7\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Now lets graph \"y=%281%2F3%29x-7\" (note: if you need help with graphing, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%281%2F3%29x-7%29+\" Graph of \"y=%281%2F3%29x-7\"\r
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\n" ); document.write( "\n" ); document.write( "So let's solve for y on the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"3x-9y=-21\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"-9y=-21-3x\" Subtract \"3+x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"-9y=-3x-21\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3x-21%29%2F%28-9%29\" Divide both sides by \"-9\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-3%2F-9%29x%2B%28-21%29%2F%28-9%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F3%29x%2B7%2F3\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Now lets add the graph of \"y=%281%2F3%29x%2B7%2F3\" to our first plot to get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%281%2F3%29x-7%2C%281%2F3%29x%2B7%2F3%29+\" Graph of \"y=%281%2F3%29x-7\"(red) and \"y=%281%2F3%29x%2B7%2F3\"(green)\r
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\n" ); document.write( "\n" ); document.write( "From the graph, we can see that the two lines are parallel and will never intersect. So there are no solutions and the system is inconsistent.
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