A = (-3, 5)
B = (-3, 2)
C = (-1, 5)
D = (1, 2)
a = Segment(B, D)
b = Segment(D, C)
c = Segment(C, A)
d = Segment(A, B)
E = Point(a)
e = Segment(C, E)
α = Angle(E, B, A)
β = Angle(B, A, C)