document.write( "Question 85713: Solve the following system of linear inequalities by graphing.
\n" ); document.write( " 3x – y < 2
\n" ); document.write( " x + y > 2
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Algebra.Com's Answer #61912 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
12.\r
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\n" ); document.write( "\n" ); document.write( "Start with the given system of inequalities\r
\n" ); document.write( "\n" ); document.write( "\"3x-y%3C2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By%3E2\"\r
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\n" ); document.write( "\n" ); document.write( "In order to graph this system of inequalities, we need to graph each inequality one at a time.\r
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\n" ); document.write( "\n" ); document.write( "So lets graph the first inequality\r
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\n" ); document.write( "\n" ); document.write( " In order to graph \"3x-y%3C2\" we need to graph the equation \"3x-y=2\" (just replace the inequality sign with an equal sign). So lets graph the line \"3x-y=2\" (note: if you need help with graphing, check out this solver)\r
\n" ); document.write( "\n" ); document.write( " \"graph%28+400%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C%282-3%2Ax%29%2F-1%29\" graph of \"3x-y=2\"\r
\n" ); document.write( "\n" ); document.write( " Now lets pick a test point, say (0,0) (any point will work, but this point is the easiest to work with), and evaluate the inequality \"3x-y%3C2\"\r
\n" ); document.write( "\n" ); document.write( " \"3%280%29-%280%29%3C2\" Plug in x=0, y=0\r
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\n" ); document.write( "\n" ); document.write( " \"0%3C2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "Since this inequality is true, we shade the entire region containing (0,0)\r
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\n" ); document.write( "\n" ); document.write( " Here is the graph of \"3x-y%3C2\" with the graph of the line(\"3x-y=2\") in red and the shaded region in green\r
\n" ); document.write( "\n" ); document.write( "(note: The red line should be a dashed line since it is not included in the region. Since the inequalityis a < sign, it tells us not to include the boundaries.)\r
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\n" ); document.write( "\n" ); document.write( "Now lets graph the second inequality\r
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\n" ); document.write( "\n" ); document.write( " In order to graph \"x%2By%3E2\" we need to graph the equation \"x%2By=2\" (just replace the inequality sign with an equal sign). So lets graph the line \"x%2By=2\" (note: if you need help with graphing, check out this
solver)\r
\n" ); document.write( "\n" ); document.write( " \"graph%28+400%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C%282-1%2Ax%29%2F1%29\" graph of \"x%2By=2\"\r
\n" ); document.write( "\n" ); document.write( " Now lets pick a test point, say (0,0) (any point will work, but this point is the easiest to work with), and evaluate the inequality \"x%2By%3E2\"\r
\n" ); document.write( "\n" ); document.write( " \"%280%29%2B%280%29%3E2\" Plug in x=0, y=0\r
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\n" ); document.write( "\n" ); document.write( " \"0%3E2\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "Since this inequality is not true, we shade the entire region that doesn't contain (0,0)\r
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\n" ); document.write( "\n" ); document.write( " Here is the graph of \"x%2By%3E2\" with the graph of the line(\"x%2By=2\") in red and the shaded region in green\r
\n" ); document.write( "\n" ); document.write( "(note: The red line should be a dashed line since it is not included in the region. Since the inequalityis a > sign, it tells us not to include the boundaries.)\r
\n" ); document.write( "\n" ); document.write( "So we essentially have these 2 regions\r
\n" ); document.write( "\n" ); document.write( " Region #1 which is the graph of \"3x-y%3C2\"\r
\n" ); document.write( "\n" ); document.write( " Region #2 which is the graph of \"x%2By%3E2\"\r
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\n" ); document.write( "\n" ); document.write( "So these regions overlap to produce this region. It's a little hard to see, but after evenly shading each region, the intersecting region will be the most shaded in.\r
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\n" ); document.write( "\n" ); document.write( "Here is a cleaner look at the intersection of regions\r
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\n" ); document.write( "\n" ); document.write( " Here is the intersection of the 2 regions represented by the dots
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