Arrangements of $4$ lines in the affine plane

The number of ways of arranging $4$ lines in the (affine) plane.

Updates

• Lower bound: $9$
  Reference unknown
  [via Number of ways of arranging n lines in the (affine) plane. - OEIS]
• Upper bound: $9$
  Reference unknown
  [via Number of ways of arranging n lines in the (affine) plane. - OEIS]