Which of the following is a line segment shown in the drawing?

∠ABX is an inscribed angle.
The measure of an inscribed angle is half the measure of the intercepted arc ⇒
arc AX = 2*∠ABX = 2 * 64 = 128°

The angle formed by the intersection of tangent and secant outside the circle equals half the difference of the intercepted arcs ⇒
∠ACB = (arc AB - arc AX)/2 = (152 - 128)/2 = 24/2 = 12°