3x-5y+6z=4 (1)
3x-2y+2z=3 (2)
-3x-3y+5z=-1 (3)
(1)-(2)
-3y+4z = 1 (4)
(2)+(3)
-5y+7z=2 (5)
5(4)-3(5)
z = 1
from (4) y=1
from (1)
3x-5+6=4
x= 1
ie
x=y=z=1