El área del trapecio es la misma que
el área del rectángulo o romboide
de base la suma de las bases del trapecio
y de altura la mitad.

t = 0 (slider from 0 to 3, step 0.01)
A = (4.7928125, -3.140625000000001)
B = (11.674531250000001, -3.140625000000001)
C = (8.668437500000001, 0.9834374999999994)
a = Line(A, B)
b = Line(B, C)
c = Line(C, a)
d = Line(A, b)
D = Intersect(c, d)
e = Ray(C, D)
E = Point(e)
f = Segment(A, B)
g = Segment(A, E)
h = Segment(E, C)
i = Segment(C, B)
j = OrthogonalLine(C, a)
F = Intersect(a, j)
caso1: AffineRatio[A, B, F] < 1.0
G = Midpoint(E, A)
H = Midpoint(C, B)
I = If(AffineRatio[G, H, Midpoint[C, F]] < 0.0, G, Midpoint[C, F])
polígono1 = If(caso1, Polygon[A, B, H, G])
α: Min[t, 1.0] * 180.0°
β: Max[t, 2.0] * 180.0°
polígono2 = If(caso1, Polygon[Rotate[C, -(β), H], Rotate[I, -(β), H], Rotate[H, -(β), H]])
polígono3 = If(caso1, Polygon[Rotate[E, α, G], Rotate[C, α, G], Rotate[I, α, G], Rotate[G, α, G]])
k = If(caso1, Segment[Rotate[E, α, G], Rotate[C, α, G]])
l = If(caso1, Segment[A, B])
m = OrthogonalLine(B, a)
J = Intersect(c, m)
K = If(AffineRatio[G, H, Midpoint[J, B]] < 0.0, G, Midpoint[J, B])
caso2: ¬caso1
polígono4 = If(caso2, Polygon[G, E, C, H])
polígono5 = If(caso2, Polygon[Rotate[K, β, H], Rotate[H, β, H], Rotate[B, β, H]])
polígono6 = If(caso2, Polygon[Rotate[A, -(α), G], Rotate[G, -(α), G], Rotate[K, -(α), G], Rotate[B, -(α), G]])
n = If(caso2, Segment[E, C])
o = If(caso2, Segment[Rotate[A, -(α), G], Rotate[B, -(α), G]])
p = Line(G, H)
L = Point(p)
s = OrthogonalLine(L, p)
M = Intersect(s, c)
q = Circle(L, M)