The value of x is 12 ( option D)
In circle geometry , there are several theorems that guides the relationship between arc and the angle substended in a circle.
Some of this theorems are ;
Angle at the centre is twice the angle at the circumference.
Angle at the center is the measure of the arc substended by it.
From the diagram,
using secant secant theorem
A = 1/2( B + C)
where A is the angle in the circle and B and C are the measures of the arc.
Therefore;
122 = 1/2( 189 + 3x + 19)
244 = 208 + 3x
3x =36
x = 12