a_2 = 9 (slider from 0 to 12, step 1)
b_2 = 10 (slider from 0 to 12, step 1)
c_1 = 11 (slider from 0 to 12, step 1)
A = (1.477883620709005, -5.961166089085341)
d = Circle(A, a_2)
B = Point(d)
e = Circle(B, b_2)
f = Circle(A, c_1)
C = Intersect(e, f, 1.0)
poly1, a, b, c = Polygon(A, B, C)
α = Angle(B, C, A)
β = Angle(C, A, B)
γ = Angle(A, B, C)