document.write( "Question 571515: using seven distinct straight lines, what is the maximum number of points of intersection? \n" ); document.write( "

Algebra.Com's Answer #368124 by KMST(5328) $\"\"$ $\"About$

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Two distinct lines can have at most 1 point of intersection. (They could have none, too).
\n" ); document.write( "With seven lines, you can combine them to make 21 different pairs, so 21 is the maximum number of points of intersection.
\n" ); document.write( "You can get the number 21 from listing and counting, or remember combinatorics and say
\n" ); document.write( " $\"C%287%2C2%29=%28matrix%282%2C1%2C7%2C2%29%29=7%2A6%2F2=21\"$ \n" ); document.write( "

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