|ZP|

|ZP'|

Z = (25, -10)
k = 3 (slider from 0.1 to 5, step 0.1)
A = (-10, 10)
B = (5, 10)
C = (5, 5)
D = (-5, 5)
E = (-5, 0)
F = (0, 0)
G = (0, -5)
H = (-5, -5)
I = (-5, -15)
J = (-10, -15)
V, a, b, c, d, e, f, g, h, i, j = Polygon(A, B, C, D, E, F, G, H, I, J)
P = Point(V)
l = Ray(Z, P)
m = Segment(Z, P)
p = Circle(Z, (k * m))
P' = Intersect(p, l)
n = Segment(Z, P')