Maximum Damage = Attack * Attack/(Attack+Defense)
Minimum Damage = Maximum Damage / 2
If you have elemental damage added to your attack, it adds that after Max Damage is calculated.
Maximum Elemental Damage = Elemental Attack - % of Elemental Resistance
Minimum Elemental Damage = Maximum Elemental Damage / 2
When you attack:
Chance to Hit = Accuracy - Dodge (Maximum of 97% Chance to Hit)
So if you have 80 Acc. and they have 10 Dodge, you have a 70% chance to hit.