Answer:
Always
Step-by-step explanation:
When two planes never intersect, they must always be parallel.
The answer can't be sometimes since planes can't sometimes intersect and be parallel.
The answer can't be never because two planes that are never parallel will intersect.
Therefore, two planes that do not intersect must always be parallel.
Always parallel
Parallel lines never intersect. Think of it like a never ending train track that goes only in a straight line. The two tracks will never cross each other!
Hope this helps!
