pr0

A = (-10.248524590163933, 5.419672131147527)
B = (-13.182950819672135, -0.41639344262295674)
C = (-2.379672131147527, -0.4491803278688584)
t1, c, a, b = Polygon(A, B, C)
O = Center(Circle[A, B, C])
D = Point(a)
M = Intersect(LineBisector[B, D], Line[A, B])
N = Intersect(LineBisector[D, C], Line[A, C])
d = Circle(A, M, N)
I = Midpoint(D, B)
J = Midpoint(D, C)
f = Segment(I, M)
g = Segment(J, N)
α = Angle(D, I, M)
β = Angle(C, J, N)
h = Segment(B, I)
i = Segment(D, I)
j = Segment(J, D)
k = Segment(J, C)