Is it possible to form a quadrilateral with 4 collinear points?
With 4 collinear points only a line can be formed. No polygon can be formed. Hence no quadrilateral can be formed with 4 collinear points.
It is possible to construct a unique quadrilateral ABCD with AB = 5cm, BC = 6cm, CD = 7cm , ∠ABC = 45∘ and ∠BCD = 55∘.