Vertex tangent to parabola
Author: Daniela Velichová

Set of all points that are intersections of parabola tangent lines 
and perpendiculars to tangents through the parabola focus F
is the tangent v in the parabola vertex V.

Part of the vertex tangent line v can be generated 
by moving the tangent point T along the parabola c.

F = (6.82, -2.04)
B = (0.5066666666666642, 10.196666666666669)
C = (0.3866666666666641, -9.963333333333335)
d = Line(B, C)
o = OrthogonalLine(F, d)
c = Parabola(F, d)
V = Intersect(c, o)
T = Point(c)
t = Tangent(T, c)
k = OrthogonalLine(F, t)
P = Intersect(t, k)
v = OrthogonalLine(V, o)