Amount Calcuation in FAH

Dear Team

Is there any way to calculate amount using some formulae in FAH ?

The business case. We are receiving one line which has amount. This amount is inclusive of tax. We need to generate Journal batch where there will be two lines 1 base amount and tax amount

I check from front end don't see any set up where we can derive amount in this way.

Please let me know if there is any way from where we can give such formulae

Thanks & regards

Santosh