Wann bilden die Vektoren von Mitte zu Mitte
ein Parallelogramm?

O = Intersect(xAxis, yAxis)
A = (5.5, 1)
B = (7, 4.5)
C = (-2, 3.5)
D = (-2, 1.5)
v1, a, b, c, d = Polygon(A, B, C, D)
u = Vector(D, A)
w = Vector(A, B)
E = Midpoint(d)
F = Midpoint(a)
G = Midpoint(b)
H = Midpoint(c)
f = Vector(E, F)
g = Vector(F, G)
e = Vector(B, C)
v = Vector(C, D)
i = Vector(G, H)
h = Vector(H, E)
j = Vector(A, C)
k = Vector(D, B)
l = Line(D, B)
m = Line(A, C)
I = Intersect(l, m)
J = (-2.6150816657653033, -1.0937784748512813)
K = (-1.1869021092482637, -1.0937784748512813)