\text{Kritérium rovnobežnosti }α,β:(α∩β=\empty)⇔(∃a,b⊂α∧∃a',b'⊂β:a∥a'∧b∥b') .

$ \pmb  α$

$\math{\pmb a}$

$\math{\pmb b}$

O = Intersect(yAxis, zAxis)
A'_{1} = OrthogonalPlane(O, zAxis)
N_{1} = (-4.014721033664298, -3.142041215655521, 0)
P = PointIn(A'_{1})
h = OrthogonalLine(P, A'_{1})
P' = Point(h)
p = Plane(P', A'_{1})
A = PointIn(A'_{1})
B = PointIn(A'_{1})
f = Line(A, P)
g = Line(P, B)
q = Plane(P', f)
i = IntersectPath(q, p)
p_1 = Plane(P', g)
l = IntersectPath(p_1, p)
k = Segment(P', P)