Final answer:
To shift a circle down 2 units, subtract 2 from the y-coordinate of the circle's center. Therefore, the new equation is A) (x-3)² + (y-7) = 36.
Step-by-step explanation:
To shift a circle down 2 units, we need to subtract 2 from the y-coordinate of the center of the circle. In the given equation, the center of the circle is (3,5). Therefore, the new equation with the circle shifted down 2 units becomes:
(x-3)² + (y-7) = 36
So, the correct option is A. (x-3)² + (y-7) = 36.