MySQL: insert values from another table into one column

I am wanting to move items from one table into another using MySQL.

This is what I currently use:

INSERT INTO items_rooms (item_id, room_id,x,y,n)  
SELECT id, room_id,x,y,z
  FROM `items_phoenix`

This works, however I am wanting to insert multiple values into one column instead of each values in different columns.

For example:

In table items_rooms, I would like values x and y from items_phoenix to be placed into one column in items_rooms.

If x = 5 and y = 2, can I save it into items_rooms like this: one column: 5.2 instead of different columns for each values?

Sorry if this is confusing!