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.
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.