Answer:
(±4√2, 0)
Step-by-step explanation:
The center-to-focus distance along the semi-major axis is the root of the difference of the squares of the semi-axes. Here, that is ...
√(6² -2²) = √32 = 4√2
Since the center of the ellipse is at (0, 0), the foci are at (±4√2, 0).