Final answer:
The sum of the exterior angles for any 2D polygon is 360 degrees, which holds true for all shapes, including triangles, as a full revolution around a shape equals 360 degrees.
Step-by-step explanation:
The sum of the exterior angles of any 2D polygon, whether it is a triangle, quadrilateral, pentagon, or any other shape, is 360 degrees. This is because when you go around a shape one complete time, you have made one revolution, which is 360 degrees. Considering a triangle, we know that its interior angles add up to 180 degrees, and this fact combined with the property of supplementary angles, which states that an interior angle added to its corresponding exterior angle equals 180 degrees, leads to the conclusion that the exterior angles of a triangle indeed sum to 360 degrees. This is true for all 2D polygons regardless of the number of sides.