Α = (1, 1)
Β = (5, 1)
a = 3 (slider from 1 to 10, step 1)
c = Circle(Α, a)
d = Circle(Β, a)
Γ, Δ = Intersect(Circle[Α, a], Circle[Β, a])
b = Segment(Α, Β)
e = Segment(Α, Γ)
f = Segment(Β, Γ)