n21

n21 = 1.43 (slider from 0 to Distance[D, E] / Distance[Intersect[d, f], E], step 0.01)
C = Intersect(xAxis, yAxis)
B = Point(Ray[C, Vector[(-1, 0)]])
d = OrthogonalLine(B, xAxis)
ControlE = Point(Ray[C, Vector[(0, -1)]])
A = Point(Ray[C, Vector[(0, 1)]])
j = Line(A, B)
f = Line(ControlE, xAxis)
D = Intersect(f, j)
b_1 = Segment(D, ControlE)
r: Distance[B, D] / n21
k = OrthogonalLine(D, f)
a = Segment(B, A)
b = Segment(D, B)
p_1 = Segment(C, A)
n_1 = Segment(C, ControlE)
E = Intersect(f, yAxis)
c = Circle(E, r)
CasillaDeEntrada1 = Textfield(n21)
t = Segment(C, Intersect[k, xAxis] - (1, 0))
e = Circle(B, r)
H = Intersect(e, f, 1)
g = Line(B, H)
M = Intersect(k, g)
R = Intersect(g, yAxis)
h = Segment(C, R)
i = Segment(M, B)
l = Segment(M, D)
m = Segment(B, R)
lugar1 = Locus(M, B)