A = (-7, -3)
D: A + (7, 0)
a = Segment(A, D)
E = Point(a)
F = (-1, 0)
e = 1.7 (slider from 0 to 3, step 0.01)
d = Segment(A, E)
c: x = 1 - e d
g = Circle(F, d)
P, C = Intersect(g, c)
i = OrthogonalLine(P, h)
B = Intersect(h, i)
PF = Segment(P, F)
PF' = Segment(B, P)
T1: "Pd/PF = " + PF' + " / " + PF + " = " + (PF' / PF)
loc1 = Locus(P, E)
loc2 = Locus(C, E)
b: x = 1 + e d
G = Intersect(g, b, 1)
H = Intersect(g, b, 2)
loc3 = Locus(G, E)
loc4 = Locus(H, E)
f = Segment(F, G)
j = OrthogonalLine(G, h)
I = Intersect(h, j)
k = Segment(I, G)