The identity element for addition property states that zero is the identity element for addition because zero added to any real number is the original number. For example,
![\begin{gathered} 1+0=1 \\ -48+0=-48 \\ 0+a=a \\ 0+19k=19k \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/pf63tn7emauugyph8ikraaus6mpz49e1f8.png)
In this case, we have:
![0+12M=12M](https://img.qammunity.org/2023/formulas/mathematics/college/fodeh1zudwc90njjzp0lfhwtsbyuqufbe5.png)
As we can see, the property mentioned above is fulfilled.
Therefore, the law illustrated by the given expression is the identity element for addition.