document.write( "Question 459028: How do you work this problem out?\r
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Algebra.Com's Answer #314841 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "1.   P * P\r\n" );
document.write( "2.   Q -> ~P    / :. ~Q\r\n" );
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document.write( "3.   P                   1      Simplification\r\n" );
document.write( "4.   ~~P                 3      Double Negation\r\n" );
document.write( "5.   ~Q                  2,4    Modus Tollens\r\n" );
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