The net ionic equation is
2H+ (aq) + 2OH-(aq)→ 2H2O (l)
explanation
2HBr (aq) +Ba(OH) (aq)→ 2H2O (l) + BaBr2 (aq)
from the chemical equation above write write the ionic equation
2H +(aq) +2Br-(aq) + Ba2+ (aq) +2OH-(aq)→ 2H2O(l) +Ba2+(aq) +2Br-
cancel the spectator ions in both side( Ba2+ and 2Br-)
the net ionic equation is therefore
2H+ (aq) + 2OH-(aq)→ 2H2O (l)