The row echelon form of a system of linear equations is given.

(a)Writethesystemofequationscorrespondingtothegivenmatrix.Usex,y.or x,y,z.or \(x_1,x_2,x_3,x_4\) asvariables.

(b)Determinewhetherthesystemisconsistentorinconsistent.Ifitisconsistent,givethesolution.

\(\begin{bmatrix}1&2&|&5\\0&1&|&-1 \end{bmatrix}\)