Let ABCD be a convex quadrilateral, with $AC\cap BD=\{O\}$ , and $OB>OD$ , $OC>OA$

Let E and F be the midpoints of (AC) and (BD), $EF\cap AB=\{J\}$ , $EF\cap CD=\{K\}$ , $CJ\cap BK=\{L\}$ . If M is the midpoint of (KJ), show that O-M-L are collinear.

Let E and F be the midpoints of (AC) and (BD), $EF\cap AB=\{J\}$ , $EF\cap CD=\{K\}$ , $CJ\cap BK=\{L\}$ . If M is the midpoint of (KJ), show that O-M-L are collinear.