document.write( "Question 936407: how many quadrilateral can be formed from 25 points out of which 7 are collinear \n" ); document.write( "

Algebra.Com's Answer #569857 by srinivas.g(540) $\"\"$ $\"About$

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4 points are needed to form a quadrilateral
\n" ); document.write( " we need to select 4 points out of 25 points
\n" ); document.write( " so no of quadrilaterals that can be formed out of 25 points = 25c4
\n" ); document.write( " = $\"%2825%2A24%2A23%2A22%29%2F%284%2A3%2A2%2A1%29\"$
\n" ); document.write( " =25*23*22
\n" ); document.write( " =12650
\n" ); document.write( "but out of 25 points , 7 points are collinear( which lies on same line)
\n" ); document.write( " so they form a line . they cannot form quadrilaterals
\n" ); document.write( " so no of quadrilaterals that cannot be formed due to collinear points = 7c4
\n" ); document.write( " = $\"%287%2A6%2A5%2A4%29%2F%284%2A3%2A2%2A1%29\"$
\n" ); document.write( " = $\"7%2A5\"$
\n" ); document.write( " =35
\n" ); document.write( " no of quadrilateral can be formed from 25 points out of which 7 are collinear are = 12650-35
\n" ); document.write( " =12615
\n" ); document.write( " Result : 12615 \n" ); document.write( "

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