O = (2, 1)
c = Circle(O, 4)
A = Point(c)
a = Line(A, O)
b = OrthogonalLine(O, a)
D, B = Intersect(c, b)
E, C = Intersect(c, a)
d = CircleSector(O, A, D)
F = (-2, -4)
G = (8.28, 6.3)
e = Line(F, G)
d' = Mirror(d, e)
G' = Mirror(G, e)
A' = Mirror(A, e)
D' = Mirror(D, e)
O' = Mirror(O, e)