Interactive Cube

Author:
matthes2
Topic:
Cube
The figure below is a cube. The polygon J K L M is a cross section of the cube. The polygon J K L M in the 3D plot translates to the line segment L I on the 2D plot. Adjust the 2D figure and see how the 3D figure changes. Does the cross section also change? What about the 2D figure and the line segment L I?
1) What is the area of J K L M at any given time? In better words is there a general equation for finding the area of J K L M.