Hello,

please help,

Given an arbitrary convex quadrilateral ABCD.

K is the center point of line segment AB.

M is the center point of line segment CD.

$\displaystyle AM \cap KD=N$, $\displaystyle BM \cap KC=L$.

Prove that: $\displaystyle Area(KLMN)=Area(\triangle AND) + Area (\triangle BCL)$.

In attachment is picture.

Thank you!