Reflecting three times
Author: R. Albers

Move H so that the blue triangle meets the green one. Compare angles.
Use E, F and G to set up a new situation. Move H again.

For help switch on the angle measurement.

Größe der Winkel

A = (8.54, 0.72)
B = (10.64, 0.74)
C = (10.34, 3.98)
poly1, c_1, a_1, b_1 = Polygon(A, B, C)
D = (5.24, -5.04)
E = (9.34, 4.14)
a = Line(D, E)
F = (5.66, 4.7)
b = Line(D, F)
G = (-0.38, 4.34)
c = Line(D, G)
A' = Mirror(A, a)
B' = Mirror(B, a)
C' = Mirror(C, a)
poly1', c', a', b' = Polygon(A', B', C')
A'' = Mirror(A', b)
B'' = Mirror(B', b)
C'' = Mirror(C', b)
poly1'', c'', a'', b'' = Polygon(A'', B'', C'')
A''' = Mirror(A'', c)
B''' = Mirror(B'', c)
C''' = Mirror(C'', c)
poly1''', c''', a''', b''' = Polygon(A''', B''', C''')
H = (2.1, 4.92)
d = Line(D, H)
A'_1 = Mirror(A, d)
B'_1 = Mirror(B, d)
C'_1 = Mirror(C, d)
poly1'_1, c'_1, a'_1, b'_1 = Polygon(A'_1, B'_1, C'_1)
α = Angle(E, D, F)
β = Angle(F, D, G)
γ = Angle(H, D, G)
h = false