Varignon Paralleogramm, geometrischer Beweis

²

A = (1.0422603791972282, 0.9500230180012508)
B = (5, 1.007105229627336)
C = (5, 3)
D = (1, 3.007105229627336)
Vieleck1, AB, BC, c, d = Polygon(A, B, C, D)
AC = Line(A, C)
g = OrthogonalLine(D, AC)
E = Intersect(AC, g)
f = OrthogonalLine(B, AC)
F = Intersect(AC, f)
G = Midpoint(D, E)
H = Midpoint(F, B)
IL = Line(G, AC)
JK = Line(H, AC)
I = Midpoint(D, A)
J = Midpoint(A, B)
K = Midpoint(B, C)
L = Midpoint(C, D)
Vieleck2, i_1, j, k, l = Polygon(I, J, K, L)
Vieleck3, DA, d_1, CD = Polygon(D, A, C)
α = Angle(AC, g)
β = Angle(AC, f)
m = Segment(D, E)
n = Segment(F, B)
DB = Line(D, B)