explain the difference account payable and trade credit

First, your School Subject is NOT Axia. That's the name of your school, not your subject.

Check these definitions of accounts payable and trade credit.

http://www.allbusiness.com/glossaries/trade-credit/4942130-1.html

http://www.allbusiness.com/4967379-1.html?query=accounts+payable&searchbox=fs