A = (-7.51, -2.27)
B = (0.19, -2.49)
C = (-2.53, 2.83)
d1, c, a, b = Polygon(A, B, C)
f = Line(A, B)
g = Line(B, C)
h = Line(C, A)
i = OrthogonalLine(C, f)
j = OrthogonalLine(B, h)
k = OrthogonalLine(A, g)
H_{a} = Intersect(g, k)
H_{b} = Intersect(j, h)
H_{c} = Intersect(f, i)
α = Angle(B, H_{c}, C)
β = Angle(C, H_{a}, A)
γ = Angle(A, H_{b}, B)
l = Segment(A, H_{a})
m = Segment(C, H_{c})
n = Segment(H_{b}, B)