A diagonal divides the parallelogram into two triangles of equal area.
True
In parallelogram ABCD, AC is the diagonal.
DE and BF are the perpendiculars from the vertices D and B respectively on AC.
The perpendiculars, DE and BF are equal, i.e., DE=BF=h
Now, area of △ACD=12×AC×DE
=12×AC×h ... (i)
Area of △ACB=12×AC×BF
=12×AC×h ... (ii)
Clearly, (i) = (ii) i.e. Area of △ACD= Area of △ACB
Hence, a diagonal divides the parallelogram into two triangles of equal area.