#919 · Combinatorics · Counting

Number of lines from points

In a plane there are $p$ points, no three of which are collinear, except for a set of $q$ points which are all collinear. Find the total number of distinct straight lines determined by these points.

~4 minAnswer checked instantlylines from pointssubtract collinear cases

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XI. Permutations and Combinations, Examples XI.b, No. 24 (part 1)

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