E is a point on the side AD produced of a parallelogram ABCD and BE intersects CD at F. Show that ΔABE ~ ΔCFB.
Given: ABCD is a parallelogram, where BE intersects CD at F. E is a point on the side AD produced.
To Prove: ΔABE ~ ΔCFB

Proof: In ∆ABE and ∆CFB,
\(\angle\)A = \(\angle\)C (Opposite angles of a parallelogram)
\(\angle\)AEB = \(\angle\)CBF (Alternate interior angles as AE || BC)
∴ ∆ABE ∼ ∆CFB (By AA similarity criterion)
Hence Proved
Fill in the blanks using the correct word given in the brackets :
(i) All circles are __________. (congruent, similar)
(ii) All squares are __________. (similar, congruent)
(iii) All __________ triangles are similar. (isosceles, equilateral)
(iv) Two polygons of the same number of sides are similar, if (a) their corresponding angles are __________ and (b) their corresponding sides are __________. (equal, proportional)



| Case No. | Lens | Focal Length | Object Distance |
|---|---|---|---|
| 1 | \(A\) | 50 cm | 25 cm |
| 2 | B | 20 cm | 60 cm |
| 3 | C | 15 cm | 30 cm |