Move any vertex to change the shape of the quadrilateral.

Q = (-3.84, 4.36)
U = (0.2, 4.8)
A = (2.2, 1.8)
D = (-3.22, -0.18)
poly1, a, b, c, d = Polygon(Q, U, A, D)
DU = Segment(U, D)
QA = Segment(Q, A)
O = Intersect(DU, QA)
e = Segment(Q, O)
f = Segment(U, O)
g = Segment(O, A)
h = Segment(O, D)
α = Angle(Q, O, D)