r = 4.18 (slider from 0 to 5, step 0.02)
A = Point(xAxis)
B = Point(xAxis)
a = Line(A, B)
O = Point(a)
b = OrthogonalLine(O, a)
D: (0, r)
c = Circle(D, O)
E = Intersect(c, b, 2)
d = Line(E, a)
F = Point(c)
e = Ray(O, F)
G = Intersect(d, e)
f = OrthogonalLine(G, d)
g = OrthogonalLine(F, f)
H = Intersect(g, f)
luogo1 = Locus(H, F)