Denote the midpoints of the convex hexagon A1A2A3A4A5A6 diagonals A6A2, A1A3, A2A4, A3A5, A4A6, A5A1 as B1,B2,B3,B4,B5,B6 respectively. Prove that if the hexagon B1B2B3B4B5B6 is convex, than its area equals to the quarter of the initial hexagon. geometryareashexagondiagonal