Focus of Parabola Construction
Author: M. Dabbs, R. Walcott

Drag point G.  Move point A.

Double click to open independently

A_1 = (-0.96, 0.98)
B = (9.82, 0.98)
a = Line(A_1, B)
D_0 = Point(a)
b = OrthogonalLine(D_0, a)
E = Point(b)
e = OrthogonalLine(E, b)
A = Point(a)
D = Point(a)
c = OrthogonalLine(A, a)
d = OrthogonalLine(D, a)
S = Mirror(D, c)
F = Point(d)
f = OrthogonalLine(F, d)
g = Segment(F, S)
G_1 = Midpoint(g)
h = OrthogonalLine(G_1, g)
H = Intersect(f, h)
loc1 = Locus(H, F)
G = Point(loc1)
i = OrthogonalLine(G, c)
J = Intersect(c, i)
M = Midpoint(J, A)
j = Segment(G, M)
k = Segment(M, S)
α = Angle(S, M, G)
l = Segment(M, J)
m = Segment(M, A)