I have 8 equations, therefore 8 rows, but I do not know what a general matrix would look like for a 3x3 magic square. What I have so far is a matrix with letters as entries. Then I set the sum of each row, column, and diagonal equal to x.

I was told by others that the matrix is 8x11. I am pretty sure I have to augment the zero vector to the matrix and use Gauss-Jordan elimination. Can you please give me any suggestions?