A = (2.4834, 4.26)
B = (-1.049, 1.2684)
C = (6.7034, -0.88)
t1, c, a_{1}, b = Polygon(A, B, C)
O = (11.8938, -2.0994)
a = 0 rad (slider from 0° to 360°, step 0.017453292519943295)
A' = Rotate(A, a, O)
B' = Rotate(B, a, O)
C' = Rotate(C, a, O)
t1', c', a', b' = Polygon(A', B', C')