There would be a few methods i'd say?
What I'd use would be the known angle of 30deg from x0,y0 to the hole and this distance (hypotenuse) which is equal to the pitch circle.
This then treats it as a right triangle and simple trig can be applied to get the lengths of the other two sides.
I won't go through the formulas as I'm the first to view and first to reply.
PM'd answer anyway to check
What I'd use would be the known angle of 30deg from x0,y0 to the hole and this distance (hypotenuse) which is equal to the pitch circle.
This then treats it as a right triangle and simple trig can be applied to get the lengths of the other two sides.
I won't go through the formulas as I'm the first to view and first to reply.
PM'd answer anyway to check