Total number of intersection points (in normal case when no two lines are parallel or no three pass through the same point) ‌10C2 But the five lines L2,L4,L6,L8,L10 are parallel, hence these lines do not intersect. Also the five lines L1,L3,L5,L7,L9 intersect at the same point, hence these lines create only one intersecting point. Number of intersecting points is: ‌10C2−‌5C2−‌5C2+1=26