% Is the following system consistent?
C=[0,3,-6,8;1,-2,3,-1;5,-7,9,0];
C
tmp=C(2,:);
C(2,:)=C(1,:);
C(1,:)=tmp;
C
C(3,:)=C(3,:)-5*C(1,:);
C
C(3,:)=C(3,:)-C(2,:);
C
% It is not consistent