Answer
Complete balanced equation is:
$Br_{2}(aq) + 2 I^{−}(aq) → 2 Br^{−}(aq) + I_{2}(aq)$
Oxidizing agent: Bromine
Reducing Agent: Iodide Ion
Work Step by Step
Electron is transferred from Iodide to Bromine, hence Br is reduced and Iodide ion is oxidized