t = 1.64 (slider from 0 to 2.5)
f(x) = If[x < t, 0, 1]
g(x) = If[x ≤ t + 1, f(x), 0]
h(x) = g(5 - x)
p(x) = If[x < t + 1, 0, (-x) + t + 1]
q(x) = If[x < t + 2, p(x), x - t - 3]
r(x) = If[x < t + 3, q(x), 0]
s(x) = h(x) + r(x)
a = Surface((u = 2, v > 3), u, -10, 10, v, -10, 10)
A: (4 - t, r(4 - t))
B: (4 - t, r(4 - t) + h(4 - t))
C: (5 - t, r(5 - t))
D: (5 - t, r(5 - t) + h(5 - t))
i = Segment(A, B)
j = Segment(C, D)