Let there be 'p' lines which are concurrent at a point A and 'q' other are concurrent at a point B. Oh, and no 2 lines are parallel.
Case 1: No line out of 'p' passes through B and similarly for 'q' and A. What are the number of points of intersection in the plane?
Case 2: There is one line which passes through both A and B. (the number of lines is still p+q) Now find number of points of intersection.
My doubt is, will the number of points of intersection still be the same?