\vec{s_{a}}

\vec{n_{a}}

\vec{s_{b}}

\vec{n_b}

Přímky a,b jsou rovnoběžné.

\vec{s_a}∦\vec{s_b}

Přímky a,b jsou různoběžné.

a

b

Polohy přímek určují body A,B,C,D. 
Polohu a velikost směrových i normálových vektorů jejich krajní body.

A = (-12, 1)
B = (-6, 5)
C = (-7, 6)
D = (-16, 0)
a = Line(A, B)
b = Line(C, D)
s_a = Vector(A, B)
s_b = Vector(C, D)
E = Midpoint(A, B)
F = Midpoint(C, D)
G = Point(a)
H = Point(b)
c = OrthogonalLine(G, a)
d = OrthogonalLine(H, b)
I = Point(c)
J = Point(d)
u = Vector(H, J)
v = Vector(G, I)
K = Midpoint(G, I)
L = Midpoint(J, H)
k: x(s_a)
l: y(s_a)
m: x(s_b)
n: y(s_b)
text2: "\vec{s_a}=(" + (LaTeX[k]) + "," + (LaTeX[l]) + ")\quad \vec{s_b}=(" + (LaTeX[m]) + "," + (LaTeX[n]) + ")"
o: x(u)
p: y(u)
q: x(v)
r: y(v)
text3: "\vec{n_a}=(" + (LaTeX[o]) + "," + (LaTeX[p]) + ")\quad \vec{n_b}=(" + (LaTeX[q]) + "," + (LaTeX[r]) + ")"
s: m / k
t: q / o
text4: "\\ \vec{s_a}∥\vec{s_b} \quad\vec{s_b}=" + (LaTeX[s]) + "\vec{s_a}\\\vec{n_a}∥\vec{n_b}\quad \vec{n_b}=" + (LaTeX[t]) + "\vec{n_a}"
M = Intersect(c, b)
N = Intersect(d, a)
e = Distance(d, c)
vzdalenostMG = Distance(M, G)
vzdalenostHN = Distance(H, N)
f = Segment(M, G)
g = Segment(H, N)
h = Circle(D, 2)
c_1 = Circle(A, 2)
O, P = Intersect(h, b)
Q, R = Intersect(c_1, a)