document.write( "Question 206974: Solve the system of equations by graphing. Then classify the system
\n" ); document.write( "3x - 9y = 81
\n" ); document.write( "2x - 6y = -4\r
\n" ); document.write( "\n" ); document.write( "I came up with (6,7)
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\n" ); document.write( "I don't undertand this stuff though.
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Algebra.Com's Answer #156482 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( "\"system%283x-9y=81%2C2x-6y=-4%29\"\r
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\n" ); document.write( "\n" ); document.write( "In order to graph these equations, we must solve for y first.\r
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\n" ); document.write( "\n" ); document.write( "Let's graph the first equation:\r
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\n" ); document.write( "\n" ); document.write( "\"3x-9y=81\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-9y=81-3x\" Subtract \"3x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2881-3x%29%2F%28-9%29\" Divide both sides by \"-9\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F3%29x-9\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the equation:\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=%281%2F3%29x-9\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the second equation:\r
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\n" ); document.write( "\n" ); document.write( "\"2x-6y=-4\" Start with the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-6y=-4-2x\" Subtract \"2x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-4-2x%29%2F%28-6%29\" Divide both sides by \"-6\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=%281%2F3%29x%2B2%2F3\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the equation:\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=%281%2F3%29x%2B2%2F3\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's graph the two equations together:\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y=%281%2F3%29x-9\" (red). Graph of \"y=%281%2F3%29x%2B2%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, which means that they will never intersect. \r
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\n" ); document.write( "\n" ); document.write( "So there are no solutions. This means that the system of equations is inconsistent.
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