mostra la parabola

A = Point(xAxis)
B = Point(xAxis)
a = Line(A, B)
F = Point(yAxis)
b = OrthogonalLine(F, a)
c = -1.2 (slider from -10 to 10, step 0.1)
C: (c, 0)
d = Line(F, C)
e = OrthogonalLine(C, d)
f = Function(1 / (4 * y(F)) * x^(2), -10, 10)
g = false