document.write( "Question 1023756: linear equations with substitution and graphing-
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Algebra.Com's Answer #639197 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
In how many ways can six students be seated in a row of 6 desks?
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document.write( "Suppose the students are A, B, C, D, E, and F\r\n" );
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document.write( "Suppose the students who insist on sitting next \r\n" );
document.write( "to each other are A and B.\r\n" );
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document.write( "Then there are two cases of arranging 5 \"things\"\r\n" );
document.write( "in a row.\r\n" );
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document.write( "Case 1:  The 5 \"things are AB, C, D, E, and F\r\n" );
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document.write( "That's 5!\r\n" );
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document.write( "Case 2: 5 \"things are BA, C, D, E, and F\r\n" );
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document.write( "That's also 5!\r\n" );
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document.write( "Answer 5! + 5! = 120 + 120 = 240 ways.\r\n" );
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\n" ); document.write( "b) if two of the six students refuse to sit next
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document.write( "First we find the number of ways they can sit\r\n" );
document.write( "without restrictions:\r\n" );
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document.write( "That's 6! = 720\r\n" );
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document.write( "Then we subtract the 240 ways from the first \r\n" );
document.write( "part of the problem:\r\n" );
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document.write( "720 - 240 = 480 ways.\r\n" );
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document.write( "Edwin
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