a = 1.26 (slider from 0 to 2)
A: (a, 0)
c = Circle(A, 2)
O: (0, 0)
J: (0, 1)
f = Ray(O, J)
B = Intersect(c, f, 1)
g = Segment(B, A)
I = Midpoint(g)
C = Intersect(xAxis, yAxis)