In the figure ABCD is a rectangle in which CD = 6 cm, AD = 8 cm.
Find the area of parallelogram CDEF.

In rectangle ABCD, CD = 6 cm, AD = 8 cm
$\therefore$ Area of rectangle $ABCD=CD\times AD$$=6\times 8=48c{m}^2$
$\because DC||ABandAB$ is produced to F and DC is produced to G
$\therefore DG||AF$
$\because$ Rectangle ABCD and || gm CDEF are on the same base CD and between the same parallels
$\therefore$ ar (||gm CDEF) = ar (rect. ABCD)
$=48c{m}^2$