**CBSE NCERT Solutions Chapter 6 Triangles Exercise 6.3 Question 3**

**3. Diagonals AC and BD of a trapezium ABCD with AB || DC intersect each other at the point O. Using a similarity criterion for two triangles, show that **

**Solution:**

**Given: **AB || DC. Diagonals of trapezium ABCD intersect at O.

**To Prove: **

**Proof: ** {Alternate Interior angles}

{Alternate Interior angles}

{Vertically Opposite angles}

Therefore, by AAA similarity criterion, ~

Therefore,

**Hence Proved**