Question

The circle below is centred at O.

AB is a tangent to this circle.
Work out the size of angle X.
Justify your answer.

Answer 1

52∘

Explanation:

Since AB is tangent to the circle and OA is a radius, that means, ∠OAB = 90∘

A triangle has 180∘, so:

180∘ - 90∘ - 38∘ = 52∘

Answer 2

52°

Explanation:

It's 180-(90+38)= 52°