hey ive been given a system of equations:

$\displaystyle w+x+y+z=5 ; w+x+y+2z=6 ; 2w+2x+2y+3z=11$

i put this into an augmented matrix and got w+x+y=4 so im guessing that this gives a solution set which is that plane..how do i write this mathematically and am i correct??

thank you