Z = (0, 0)
a = 1.5 (slider from 0 to 3, step 0.1)
A = (0.1502495737075283, 1.3011611646968944)
B = (1.4254508566164583, -0.9250376851271691)
b = Line(A, B)
P = Point(b)
c = Ray(Z, P)
abstandZP = Distance(Z, P)
TextZP: "\overline{" + (Name[Z]) + (Name[P]) + "} \, = \, " + abstandZP
d = Circle(Z, a * Distance[Z, P])
P' = Intersect(d, c)
Ortslinie1 = Locus(P', P)