A = (1, 3.8)
B = (2, 5)
C = (3, 6)
a = 0 (slider from -5 to 5, step 0.1)
E = (4, 6.8)
F = (5, 7.4)
G = (3.0023137433623295, 5.800639105686412)
d: 1.0 * y = a * x + 5.8 - 3.0 * a
H: (1.0, 5.8 - 2.0 * a)
I: (2.0, 5.8 - a)
J: (4.0, 5.8 + a)
K: (5.0, 5.8 + 2.0 * a)
h = Segment(A, H)
i = Segment(B, I)
g = Segment(C, G)
j = Segment(J, E)
k = Segment(K, F)