$\scalebox{2} {%n}$

$\scalebox{2} {%n}$

$\scalebox{2} {%n}$

$\scalebox{2} {%n}$

$\scalebox{2} {%n}$

A = Intersect(xAxis, yAxis)
D = Point(xAxis)
f = OrthogonalLine(D, xAxis)
B = Point(yAxis)
g = OrthogonalLine(B, yAxis)
C = Intersect(f, g)
h = Segment(B, D)
i = Segment(A, C)
j = Segment(B, A)
k = Segment(A, D)
l = Segment(D, C)
m = Segment(B, C)
O = Intersect(h, i)