s

A = (-6.14, 4.72)
B = (2.72, 4.7)
g = Line(A, B)
C = (-7.94, 6.4)
f_1 = OrthogonalLine(C, g)
C' = Mirror(C, g)
e = OrthogonalLine(C, f_1)
f = OrthogonalLine(C', f_1)
D = Intersect(f_1, g)
s = Segment(C, D)
i = Segment(D, C')
α = Angle(s, g)