plss help me with this I don't even know where to start to solve it

From the balanced equation of the reaction, the coefficients of the reactants and products are 1:2:1.
A balanced equation of a chemical reaction is an equation which balances the atoms of each element on the reactants as well as the products side of a chemical reaction.
The balanced equation of the reaction that occurs when magnesium bromide is heated is shown below:
[tex]MgBr_2 \rightarrow Br_2+Mg [/tex]
Therefore, the coefficients of the reactants and products are 1:2:1.
Learn more about balanced equations at: https://brainly.com/question/26227625