document.write( "Question 939432: Prove that 6C2 + 6C3 = 7C3\r
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\n" ); document.write( " 2!4! 3!3! \r
\n" ); document.write( "\n" ); document.write( "Step 2 6! 4*6!
\n" ); document.write( " ---- + -----
\n" ); document.write( " 4*3!3! 4*3!3! \r
\n" ); document.write( "\n" ); document.write( "Step 3 5*6!
\n" ); document.write( " ------
\n" ); document.write( " 4*3!3!
\n" ); document.write( " Step 4 7! 7*6!
\n" ); document.write( " ---- = -----
\n" ); document.write( " 3!4! 4*3!3!
\n" ); document.write( "Step 5 5*6! 7*6!
\n" ); document.write( " ----- not equal -----
\n" ); document.write( " 4*3!3! 4*3!3!
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Algebra.Com's Answer #573217 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Prove that 6C2 + 6C3 = 7C3\r\n" );
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document.write( "That is prove that\r\n" );
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document.write( "        6!         6!         7!\r\n" );
document.write( "     -------- + -------- = --------\r\n" );
document.write( "     2!(6-2)!   3!(6-3)!   3!(7-3)!         \r\n" );
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document.write( "which simplifies to:\r\n" );
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document.write( "          6!    6!     7!\r\n" );
document.write( "         --- + ---- = ----\r\n" );
document.write( "         2!4!  3!3!   3!4!\r\n" );
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document.write( "Step 1    6!    6! \r\n" );
document.write( "         --- + ---- \r\n" );
document.write( "         2!4!  3!3! \r\n" );
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document.write( "Your first fraction is wrong on step 2. You needed a\r\n" );
document.write( "3 factor to make the 2! into a 3!\r\n" );
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document.write( "Step 2    6!   4*6!               3*6!       4*6!\r\n" );
document.write( "        ---- + ----- should be --------  +  -----\r\n" );
document.write( "       4*3!3!  4*3!3!          3*2!4*3!     4*3!3! \r\n" );
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document.write( "Step 3                            3*6!       4*6!     \r\n" );
document.write( "                               --------  +  -----\r\n" );
document.write( "                                  3!4!       4!3!\r\n" );
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document.write( "Step 4                            3*6! + 4*6! \r\n" );
document.write( "                                 -------------\r\n" );
document.write( "                                     3!4!\r\n" );
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document.write( "Step 5                               7*6!\r\n" );
document.write( "                                    ------\r\n" );
document.write( "                                     3!4!\r\n" );
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document.write( "Step 6                                7! \r\n" );
document.write( "                                    ------\r\n" );
document.write( "                                     3!4!\r\n" );
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document.write( "Edwin
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