% Is the following system consistent?
B=[1,-2,1,0;0,2,-8,8;-4,5,9,-9];
B
B(3,:)=B(3,:)+4*B(1,:);
B
B(2,:)=B(2,:)/2;
B
B(3,:)=B(3,:)+3*B(2,:);
B
% It is consistent.