document.write( "Question 305434: I am working with linear equations and graphing them on a number line. The problem is I am not sure when to use the () or []. Is there a rule for to know when and how to use the symbols? \n" ); document.write( "

Algebra.Com's Answer #218655 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Use [ or ] if the endpoint is contained in the interval,\r\n" );
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document.write( "and use ( or ) if the endpoint is not included.\r\n" );
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document.write( "For the graph of , where the 4 is included but the\r\n" );
document.write( "-3 is not, you have this:\r\n" );
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document.write( "-------------(===========================]----------\r\n" );
document.write( "-6  -5  -4  -3  -2  -1   0   1   2   3   4   5   6\r\n" );
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document.write( "and the interval notation is an abbreviation of this graph:\r\n" );
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document.write( "(-3,4]\r\n" );
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document.write( "----------------------------------\r\n" );
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document.write( "For the graph of , where the -3 is included but the\r\n" );
document.write( "4 is not, you have this:\r\n" );
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document.write( "-------------[===========================)----------\r\n" );
document.write( "-6  -5  -4  -3  -2  -1   0   1   2   3   4   5   6\r\n" );
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document.write( "and the interval notation is an abbreviation of this graph:\r\n" );
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document.write( "[-3,4)\r\n" );
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document.write( "----------------------------------\r\n" );
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document.write( "For the graph of , where both the -3 and the 4 are\r\n" );
document.write( " included, you have this:\r\n" );
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document.write( "-------------[===========================]----------\r\n" );
document.write( "-6  -5  -4  -3  -2  -1   0   1   2   3   4   5   6\r\n" );
document.write( "\r\n" );
document.write( "and the interval notation is an abbreviation of this graph:\r\n" );
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document.write( "[-3,4]\r\n" );
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document.write( "----------------------------------\r\n" );
document.write( "\r\n" );
document.write( "For the graph of , where neither the -3 nor the 4 is \r\n" );
document.write( "included, you have this:\r\n" );
document.write( "\r\n" );
document.write( "-------------(===========================)----------\r\n" );
document.write( "-6  -5  -4  -3  -2  -1   0   1   2   3   4   5   6\r\n" );
document.write( "\r\n" );
document.write( "and the interval notation is an abbreviation of this graph:\r\n" );
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document.write( "(-3,4)\r\n" );
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document.write( "Edwin

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