Given a quadrilateral ABCD such that vector AD = BC, point M is the midpoint of side BC.

Given a quadrilateral ABCD such that vector AD = BC, point M is the midpoint of side BC. Lines AM and CD intersect at point K. Among vectors AB, AD, BM, CM and CK indicate pairs: 1) collinear vectors 2) co-directional vectors 3) oppositely directed vectors 4) vectors having equal absolute values 5) equal vectors

1) pairs of collinear vectors: BM and CM; AB and CK; BM and AD; AD and CM;
2) a pair of co-directional vectors: AB and CK;
3) a pair of oppositely directed vectors: BM and CM;
4) pairs of vectors having equal modules: BM and CM; AB and CK (since the quadrilateral is a parallelogram, since its opposite sides are pairwise parallel, then the triangles ABM and KCM are equal according to 2 signs: in two corners, these are pairs of vertical and criss-crossing angles, and the side between them);
5) a pair of equal vectors: AB and CK.