Find the solution to the system of equations.
6x + y - 2z = 18
6x - y - 2z = 18
y + z = 3
A. x = 4, y = 1, z = 2
B. x = 4, y = 0, z = 3
C. x = 1, y = 0, z = 3
D. x = 4, y = 1, z = 4