Question

O is the centre of a circle AT is the tangent to the circle T is the point of contact what is the measure of angle OTA

Answer 1

Answer:

It's a right angle.

Just consider the symmetry!

Answer 2

Angle OTA = 90°

Here OT is the radius of the circle with centre O. Radius OT being the shortest line from the centre to the tangent is perpendicular.

I hope you are familiar with the chapter 10: circles..first theorem in this chapter(theorem 10.1) states that the tangents at any point of a circle is perpendicular to the radius through the point of contact ( if not familiar with this theorem,keep it in mind,it may help you :) )

Hope it helps!