A_1 = (2.66, 0.5)
B_1 = (5.42, -2.66)
c = Circle(A_1, B_1)
B = Point(c)
f = Line(B, A_1)
A = Intersect(c, f, 2)
C = Point(c)
poly1, c_1, e, d = Polygon(C, A, B)
α = Angle(A, C, B)