document.write( "Question 381352: Could someone please help? I need to graph a system of linear inequalities, then test to see what satisfies both. Here is the system:
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document.write( " x+y>4
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document.write( " x+y<-1
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document.write( "Here's what I have done so far:
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document.write( "For Line 1, the first inequality:
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document.write( "x-intercept is (4,0) and y-intercept is (0,4)\r
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document.write( "For Line 2, the second inequality:
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document.write( "x-intercept is (-1,0) and y-intercept is (0,-1).\r
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document.write( "Ok, both these lines are dashed lines, since neither are equal, and therefore included, so I end up with two parallel dashed lines. My problem: I can't find an answer to satisfy BOTH inequalities, so I don't know what to shade in as \"true\".
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document.write( "Can someone please set me straight and tell me what I am doing wrong? Thank you!!! \n" );
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Algebra.Com's Answer #270476 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! Consider this: Let z=x+y be some number\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the system \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x+y>4 \n" ); document.write( "x+y<-1\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "is really saying\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "z > 4 \n" ); document.write( "z < -1\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So the question is now: what number (z) is BOTH greater than 4 AND less than -1? This is impossible. Since no number exists, this means that there are no solutions to the system of inequalities above.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So there are no solutions to the system \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x+y>4 \n" ); document.write( "x+y<-1\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Visually, you'll get the following\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Where the blue shaded region refers to the solution set of x+y>4 and the red shaded region refers to the solution set of x+y<-1. Since the two regions will NEVER intersect (at any point in the xy plane), this means that the solution set is empty.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Also, feel free to check out my tutoring website\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Jim \n" ); document.write( " |