Question

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Answer 1

(3,240) says that you move 3 units out from 240 degrees.

that is that same as the following points
(3,240+360)
(3, 240 - 360)

you can also move negative distance
(-3, 240 + 180)

Answer 2

so it can be (-3,420) , ( 3,600) and (3, -120) ??