We'll find the augmented matrix first:

Put in all the 1 or -1 coefficients where the coefficient is 
understood.

Put in 0 coefficients for x in the third equation and for y in the
4th equation.

 

Erase all the letters and replace the equal signs by a verticle bar
and put parentheses around the whole thing:

 

That's the augmented matrix.

-----------------------------------------------------

To find the AX=B equation

Matrix A is the 4x4 matrix of coefficients
the numbers left of the bar in the augmented matrix:

 

The matrix X is the 4x1 matrix of letters,
(unknowns or variables), in the same order
they appear in the original system of 
equations:



The matrix B is the 4x1 matrix of numbers that
appear on the right of the equal signs,  and
right of the bar in the augmented matrix:



So the equation  is

  

You do the other one.  It's the same way.  Just follow the same
steps as above.

Edwin