4.已知非齐次线性方程组-|||- ) (x)_(1)+5(x)_(2)-(x)_(3)-(x)_(4)=-1 (x)_(1)-2(x)_(2)+(x)_(3)+3(x)_(4)=3 3(x)_(1)+8(x)_(2)-(x)_(3)+ .-|||-系数矩阵记为A,增广矩阵为A,则-|||-r(A)= __ -(overrightarrow (A))= __-|||-并借此判定该非齐次线性方程组解的情况为-|||-__ (最后一空填入唯一解或无穷解或无解)