document.write( "Question 528315: how many planes are determined by 9 points no three of which are collinear?
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Algebra.Com's Answer #349251 by Edwin McCravy(20060) $\"\"$ $\"About$

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How many planes are determined by 9 points no three of which are collinear?
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document.write( "That depends on how many, if any, groups of four or more points lie in the \r\n" );
document.write( "same plane.\r\n" );
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document.write( "At one extreme, if all 9 points lie in the same plane, then they determine \r\n" );
document.write( "only one plane.\r\n" );
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document.write( "At the other extreme, if no group of 4 points lie in the same plane, then\r\n" );
document.write( "every group of three points would determine a plane. So there would be\r\n" );
document.write( " C(9,3) = 84 planes.\r\n" );
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document.write( "So the number of planes determined could vary from 1 to 84, depending\r\n" );
document.write( "on how many groups of 4 or more points lie in the same plane.\r\n" );
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document.write( "Edwin

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