It appears that you are describing a geometric figure, but without a diagram or more detailed context about points A, B, C, E, and F, I'm unable to clearly determine the configuration or relationship between these points.
To determine the length of CE, I would typically need more information about the geometry of the situation, such as whether these points lie on a specific shape (like a triangle or rectangle) or whether there is a defined relationship between the lengths given.
If AB = 12 units and BC = 16 units, we can only proceed if we know the relationship of point E to these segments or if there are any additional angles, ratios, or figures involved.
Could you please provide more context or details regarding the points and their placement?