document.write( "Question 84155: Graph the inequality
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Algebra.Com's Answer #60595 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Graph the inequality\r\n" );
document.write( "x - 3y < 9\r\n" );
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document.write( "First form the equation of the boundary line,\r\n" );
document.write( "which is found by replacing the < by =\r\n" );
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document.write( "        x - 3y = 9\r\n" );
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document.write( "Draw this line by find the intercepts (0,-3) and (9,0)\r\n" );
document.write( "Draw the line dotted because the inequality is\r\n" );
document.write( "< and not <\r\n" );
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document.write( "Now we only have to decide whether we are to shade the \r\n" );
document.write( "upper side of the line or the lower side of it. To do\r\n" );
document.write( "this we pick any point which IS NOT on the line. Say we\r\n" );
document.write( "choose as a test point the point (2,3) marked below with \r\n" );
document.write( "an o, which is above the line.\r\n" );
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document.write( "Now we substitute \r\n" );
document.write( "(x,y) = (2,3) into the inequality\r\n" );
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document.write( "       x - 3y < 9\r\n" );
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document.write( "If we get a true inequality, then we will shade the\r\n" );
document.write( "same side of the line that the test point is on.  If\r\n" );
document.write( "we get a false equationj, we shade the other side:\r\n" );
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document.write( "       x - 3y < 9\r\n" );
document.write( "     2 - 3(3) < 9\r\n" );
document.write( "        2 - 9 < 9\r\n" );
document.write( "           -7 < 9\r\n" );
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document.write( "This is true, so we shade the same side of the line\r\n" );
document.write( "which the test point that we picked is on, namely the\r\n" );
document.write( "upper side.  I can't shade on here but you can on\r\n" );
document.write( "your paper:  \r\n" );
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document.write( "Edwin
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