A = (0.11887600204673587, 3.491949513900736)
B = (6.096549548012963, 3.6305048609926684)
a = Segment(A, B)
D = (-0.9103922906361908, -0.7042981408835076)
b = Segment(A, D)
c = Line(D, a)
D_1 = Midpoint(a)
d = OrthogonalLine(D_1, a)
E = Intersect(c, d)
C = Mirror(D, d)
e = Segment(B, C)
đa giác1, a_1, b_1, c', c_1 = Polygon(A, B, C, D)
α = Angle(B, C, D)
β = Angle(C, D, A)