document.write( "Question 165449: Solve the system by graphing.\r
\n" ); document.write( "\n" ); document.write( "x + y = 3
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Algebra.Com's Answer #121953 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"system%28x%2By=3%2Cx%2By=-1%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( "\"x%2By=3\" Start with the first equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=3-x\" Subtract \"x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B3\" 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=-x%2B3\".\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( "\"x%2By=-1\" Start with the second equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-1-x\" Subtract \"x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x-1\" 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=-x-1\".\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=-x%2B3\" (red). Graph of \"y=-x-1\" (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. So there are no solutions. This means that the system of equations is inconsistent.\r
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