linear algebra – Is this augmented matrix coherent? If so, is the solution unique?

Consider the following augmented matrices in which * denotes an arbitrary number and ◼️ denotes a number other than zero. Determine whether the given matrices are consistent. If it is coherent, is the solution unique?

Matrix A

Matrix B

These matrices are similar to this question, but I have trouble understanding the answers to this article and how they came to this answer. Any help with understanding the setup here, as well as tips for thinking about solutions, is greatly appreciated.