Balance
This is an example of formal balance because it is symmetrical. Although you can't see the entire room the way the ottoman is set up and the lamps on either side of the bed are showing you can tell they are symmetrical. I'm assuming that the nightstand and plant are the same on the other side of the bed as well because the composition of the room implies that everything was carefully placed and designed.
This is an example of formal balance because the bed and room are symmetrical. Even though the bookshelves have different objects on both sides the weight of the two sides are equal.
Q