**Circles ncert solutions Chapter 10 Exercise 10.2 Question 4**

**4. Prove that the tangents drawn at the ends of diameter of a circle are parallel.**

**Solution:**

It is given that O is the center of circle and we have two tangents AD and CE to the circle.

We want to prove that AD || CE.

We can say that is equal to because tangent is perpendicular to radius. **(1) **

We can also say that is equal to because tangent is perpendicular to radius. **(2)**

AC is given as the diameter of circle. **(3)**

From **(1), (2) and (3)**, we can say that AC is the transversal and . Therefore, and are co-interior angles. Therefore, AD || CE.

**Hence Proved**