how to get last row of record set in mysql

Question

i execute following query to get the below result set:

SELECT del_trs_id, dealer_id, balance_amount from dealer_transections order by dealer_id, del_trs_id;

del_trn_id    dealer_id     balance_amount
1             1             500
2             1             600
5             1             800
10            1             1000
3             2             300
4             2             310
6             2             350
7             2             380
8             2             670
9             2             900  

actully i want to get only last row of dealer_id 1, 2 (del_trn_id 10 and 9) which is current balance of a dealer. can any one help?