s_a

s_b

s_c

A = (6, 5)
B = (3, -4)
C = (10, -3)
t1, c, a, b = Polygon(A, B, C)
D = Midpoint(c)
E = Midpoint(b)
F = Midpoint(a)
f = Line(D, C)
g = Line(F, A)
h = Line(B, E)
d = false
e = false
i = false
S = Intersect(f, g)