A = (-8, 0)
c = Circle(A, 1)
B: (x(A) + 1, y(A))
a = Tangent(B, c)
α = 7.3 (slider from -7 to 9, step 0.1)
C: (α, tan(α))
B' = Rotate(B, α, A)
b = Line(A, B')
D = Intersect(a, b)
d = Segment(A, D)
e = CurveCartesian(t, tan(t), t, -7, α)
f = Segment(D, C)
l = CurveCartesian(((0.2 - t / 50) * cos(t)) + x(A), ((0.2 - t / 50) * sin(t)), t, α, 0)
m = Segment(A, B')
n = CurveCartesian(((0.2 + t / 50) * cos(t)) + x(A), ((0.2 + t / 50) * sin(t)), t, 0, α)