Reflection twice
Author: R. Albers

Take point E and move it to the left. Line e stays.
What will happen to the green triangle?

Die linke Spiegelachse ist fest. Bewegen Sie den Punkt E nach links.
In welche Richtung wird sich das grüne Dreieck bewegen?

A = (6.659999999999999, -2.6000000000000023)
B = (10.42, -2.5800000000000027)
C = (10, 0)
poly1, c, a, b = Polygon(A, B, C)
D = (4.5200000000000005, -4.74)
E = (10.34, 4.88)
d = Line(D, E)
F = (2.72, 3.08)
e = Line(D, F)
A' = Mirror(A, d)
B' = Mirror(B, d)
C' = Mirror(C, d)
poly1', c', a', b' = Polygon(A', B', C')
A'' = Mirror(A', e)
B'' = Mirror(B', e)
C'' = Mirror(C', e)
poly1'', c'', a'', b'' = Polygon(A'', B'', C'')