Answer:
The balanced equation is:
B₂Br + 6 HNO₃ → 2 B(NO₃)₃ + 3 HBr
In the balanced equation, the coefficient 6 is added in front of HNO₃ to balance the number of nitrogen and oxygen atoms on both sides of the equation. The coefficients 2 and 3 are added in front of B(NO₃)₃ and HBr respectively to balance the number of boron, nitrogen, oxygen, and hydrogen atoms on both sides of the equation.