SOLUTION: If I have a point on the unit circle at (-5/13, -12/13) made by positive angle theta, than how do I add/subtract pi?

You have a unit circle and a given point on it.


When you add/subtract , it is the same as to rotate the unit circle by the angle    anticlockwise or clockwise, respectively.



In any case, your point will be transformed to the opposite point in the circle,

changing the original x- and y- coordinates to opposite numbers.



In your case, the transformed point will be  (5/13,12/13).      ANSWER