Solving System use gauss Jordan reduction to transform the augmented matrix of each system in Problems 1-3

Question:

Solving System use gauss Jordan reduction to transform the augmented matrix of each system in Problems 1-3 to RREF. Use it to discuss the solutions of the system (i.e., no solutions, a unique solutions, or infinitely many solutions).
1. x + y = 4
x - y = 0
2. y = 2x
y = x + 3
3. x + y + z = 0
y + z = 1