Respuesta :

Answer:

Option (C)

Step-by-step explanation:

Since angle 'a' is the inscribed angle of the given triangle

Therefore, angle measure of the intercepted arc will be equal to the double of the inscribed angle.

x = 2a ⇒ a = [tex]\frac{x}{2}[/tex]

By the tangent-chord theorem,

"Angle between a chord and tangent measure the half of the angle measure of intercepted minor arc"

[tex]\frac{x}{2}[/tex] = 40°

Therefore, a = [tex]\frac{x}{2}[/tex] = 40°

Option (C) will be the answer.