Yes
Step-by-step explanation:
This chemical equation:

is balanced, because the number of atoms of each element is the same on the reactant side and on the product side. In fact:
- Mg: one atom on the left, one on the right
- I: 2 atoms on the left, and 2 on the right
- Br: 2 atoms on the left, and 2 on the right
So, the reaction is balanced.