Pappus Theorem
Author: Hans-Peter Schröcker
Date: July 21, 2010

A = (2.1281398127680453, -1.6845250112855825)
B = (5.773643364631305, 2.2932107391506147)
C = (7.596395140562936, -4.457735147153071)
D = (5.098498656129412, -5.720218052339051)
a = Line(A, B)
b = Line(B, C)
c = Line(C, D)
d = Line(D, A)
e = Line(A, C)
f = Line(B, D)
E = (-1.56, 6.9)
F = (-7.995143127406082, -9.387886499806386)
G = (18.84137148131037, -9.303849829022523)
g = Line(F, G)
H = Intersect(g, a)
I = Intersect(g, c)
J = Intersect(g, f)
K = Intersect(g, d)
L = Intersect(g, b)
M = Intersect(g, e)
h = Segment(A, D)
i = Segment(D, C)
j = Segment(C, B)
k = Segment(B, A)
N = (1.3287395178176442, -15.153138262262546)
l = Line(H, N)
m = Line(N, M)
O = Point(m)
n = Line(L, O)
P = Intersect(l, n)
p = Segment(N, P)
q = Segment(P, O)
r = Line(I, O)
s = Line(K, N)
t = Line(P, J)
Q = Intersect(s, r)
a_1 = Segment(N, Q)
b_1 = Segment(O, Q)