f: y = (-(x - 1)^(2)) + 2
g: y = x - 3
A_n = Point(g)
p = OrthogonalLine(A_n, xAxis)
C_n = Intersect(f, p)
I = Midpoint(C_n, A_n)
c = Circle(I, 1.5)
q = OrthogonalLine(I, yAxis)
B_n, D_{1} = Intersect(c, q)
r = Segment(D_{1}, B_n)
v3, a_n, d_n, c_n, d_{1} = Polygon(A_n, B_n, C_n, D_{1})