document.write( "Question 480484: how many distinct lines can be drawn through 15 point no 3 of with are in the same straight line? \n" ); document.write( "
Algebra.Com's Answer #329053 by Edwin McCravy(20055)\"\" \"About 
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document.write( "If the 15 points are labeled A,B,C,D,E,F,G,H,I,J,K,L,M,N,O then since\r\n" );
document.write( "two points determine a line, and since order doesn't matter (since AB\r\n" );
document.write( "and BA determine the same line), the answer is \"15 things choose 2\" which\r\n" );
document.write( "is called \"the number of combinations of 15 things taken 2 at a time\",\r\n" );
document.write( "which is sometimes written 15C2, or C(15,2) or 15C2 or \"%28matrix%282%2C1%2C15%2C2%29%29\".\r\n" );
document.write( "                                                                                         \"7\"\r\n" );
document.write( "It is calculated as \r\n" );
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document.write( "Edwin
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