a = 10 (slider from 0 to 12, step 1)
b = 4 (slider from 0 to 12, step 1)
c = 7 (slider from 0 to 12, step 1)
A = (11.595373186664201, 0.42106049805579615)
B = Point(Circle[A, a])
f = Segment(A, B)
e = Circle(B, b)
Γ = Point(e)
g = Segment(B, Γ)
h = Circle(Γ, c)
Δ = Point(h)
i = Segment(Γ, Δ)
j = Segment(A, Δ)
k = Segment(A, Γ)
l = Segment(B, Δ)
Ι = Intersect(k, l)
Κ = Intersect(k, l)
η = Angle(Γ, Ι, B)