If 20 lines are drawn in a plane such that no two of them are parallel and no three are concurrent. In how many points will they intersect each other ?

If n straight lines in a plane are such that no two of them are parallel and no three of them are concurrent, prove that they intersect each other in (n(n-1))/2 points.

If n lines are drawn in a plane such that no two of them are parallel and no three of them are concurrent, such that these lines divide the planein 67 parts, then find number of different points at which these lines will cut.

If n lines are drawn in a plane such that no two of them are parallel and no three of them are concurrent, then find number of different points at which these lines will cut.

Six straight lines are in a plane such that no two are parallel & no three are concurrent. The number of parts in which these lines divide the plane will be

No two equipotential intersect each other. Why?