Two tangents are drawn to a circle. if the tangent intercepts a major arc of 204 degrees, what is the measure of the angle formed by the tangent

I think your question needs to be worded differently.
The tangents would intercept a major arc (204) and a minor arc (156).
The angle formed would be one half of the major arc.
The angle would measure (1/2) (204-156) = 24 degrees

Horizontal change or the change of x