E is the mid-point of the side AD of the trapezium ABCD with . A line through E drawn parallel to AB intersect BC at F. Show that F is the mid-point of BC. [Hint: Join AC]
Solution.
Given: ABCD is trapezium and
Constructions: Join AC which intersect EF at O
Proof: In , E is the mid-point of line AD and .
By mid-point theorem, O is mid-point of AC
∴ In , as O is mid-point of AC
(mid-point theorem)
Hence again by mid-point theorem, F is the mid-point of BC.
Hence proved