Question
Show that 
.
OR
Show that 
and give a geometrical interpretation of it.
Solution
L.H.S. = 
Gemetrical Interpretation
Let O be the point of intersection of diagonals AC and BD of || gm ABCD.
Let 
implies that the area of || gm ABCD is twice the area of the || gm whose adjacent sides are semi-diagonals of the first parallelogram.
