document.write( "Question 146412: Graph the inequality on a plane\r
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Algebra.Com's Answer #106890 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"4x%2B5y%3C=20\" Start with the given inequality.\r
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\n" ); document.write( "\n" ); document.write( "\"4x%2B5y=20\" Replace the inequality sign with an equals sign.\r
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\n" ); document.write( "\n" ); document.write( "\"5y=20-4x\" Subtract \"4x\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=%2820-4x%29%2F%285%29\" Divide both sides by \"5\" to isolate \"y\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%284%2F5%29x%2B4\" Rearrange the terms and simplify.\r
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\n" ); document.write( "\n" ); document.write( "So in order to plot \"4x%2B5y%3C=20\" or \"y%3C=-%284%2F5%29x%2B4\" (which is the same thing), we need to plot the equation \"y=-%284%2F5%29x%2B20\" first.
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C-%284%2F5%29x%2B4%29+\" Graph of \"y=-%284%2F5%29x%2B4\"\r
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\n" ); document.write( "\n" ); document.write( "Now plug in a test point (0,0) into the inequality \"y%3C=-%284%2F5%29x%2B20\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%3C=-%284%2F5%29x%2B4\" Start with the given inequality.\r
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\n" ); document.write( "\n" ); document.write( "\"0%3C=-%284%2F5%29%2A%280%29%2B4\" Plug in \"x=0\" and \"y=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"0%3C=4\" Evaluate and simplify.\r
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\n" ); document.write( "\n" ); document.write( "Since the inequality is true, this means that we shade the entire region that contains the point (0,0)\r
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\n" ); document.write( "\n" ); document.write( "In other words, we simply shade the entire region that is below the line.\r
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\n" ); document.write( "\n" ); document.write( " Graph of \"y%3C=-%284%2F5%29x%2B4\" with the shaded region in green\r
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