H = (0, 0)
E = (0, -3)
F = (3, -3)
G = (3, 0)
a = Segment(H, E)
b = Segment(F, E)
c = Segment(F, G)
d = Segment(G, H)
D = (0, 4)
e = Segment(H, D)
f = Segment(D, G)
B = (-3, 0)
g = Segment(H, B)
h = Segment(B, D)
i = OrthogonalLine(B, h)
k = Circle(B, Segment[H, G])
C = Intersect(k, i, 2)
j = Segment(C, B)
α = Angle(D, B, C)
l = Segment(C, B)
D_1 = Point(k)
I = Point(k)
p = CircleArc(B, D_1, I)
m = Segment(C, D)
β = Angle(D, H, B)
q = Circle(G, Segment[E, H])
n = OrthogonalLine(G, f)
J = Intersect(q, n, 2)
r = Segment(J, G)
K = Point(q)
L = Point(q)
s = CircleArc(G, K, L)
γ = Angle(J, G, D)
t = Segment(D, J)