Comments below.GrandadIn the figure , ABCD is a parallelogram . AE=BF and C is parallel to FH . Prove that
(1) EFCD is a parallelogram
(2) GHFC is a parallelogram
(3) parallelogram GHFC and ABCD are equal in area
My work :
(1) BC // AD , AE=BF , AD=BC
(corresponding angle) No. You mean
DE// CF , AF// DC
Hence , EFCD is a paralleogram. Apart from that this is fine.
(2) DH // CF , CG//HF
Hence , GHFC is a parallelogram . OK.
(3) not really sure .Use the result from your previous post: parallelograms on the same base and between the same parallels are equal in area. Look first at CFDE and CFGH; then at CDEF and CDAB. (Note the bold type.)