business area-payment

Experts:- If one company code making the payment for the two business area, at that time balance sheet, is tally or not (intererviewr says) is not tally,

why what is the reason. this is my client (can u give ur ideas for this question

And aslo if the business area,is making the payment 2business area,what are the entries comes, and give that entries, ( assinge immdiately points)