A = (-5, 1)
B = (-2, 5)
C = (-2, 0)
D = (1, 4)
f = Segment(A, B)
g = Segment(C, D)
E = (-2, 1)
F = (1, 0)
h = Segment(A, E)
i = Segment(E, B)
j = Segment(C, F)
k = Segment(F, D)
α = Angle(B, E, A)
β = Angle(D, F, C)