C = (-1.1266707449839368, 4.7851890660478436)
A = (-4.912218107434298, 1.0475600246411585)
B = (6.636097264091487, 1.1913149877721847)
đa giác1, c_1, c, b = Polygon(C, A, B)
α = Angle(A, C, B)
a = Distance(b, c_1)