You can GUESS at, but not be sure of, pipe locations by looking at where the sink is now, where the bathrooms are, where the cleanouts are , and where the main drain leaves the house headed for the street.
This may be more than you want to take on. Given the short distance, one way to do it is to run the drain on the inside of the wall, sloped down hill and running through the cabinets. Not ideal, but you may need a plumber to do the work which might be entailed under the slab.
Just to further compound the issue, do you know if you have a conventional slab, or a post-tensioned slab, which cannot be cut into.??