# Are these two matrices equivalent?

I am supposed to row reduce a matrix to reduced row echelon form. $$\begin{bmatrix} 1 & 2 & 4 & 8\\ 0 & 0 & 1 & 4\\ 0 & 0 & 0 & 0 \end{bmatrix}$$

I have tried the following: 4 times row 2 - row 1 gives the following matrix: $$\begin{bmatrix} 1 & 2 & 0 & 8\\ 0 & 0 & 1 & 4\\ 0 & 0 & 0 & 0 \end{bmatrix}$$

I checked the answer in the back of the textbook I am using and it says that the answer is $$\begin{bmatrix} 1 & 2 & 0 & -8\\ 0 & 0 & 1 & 4\\ 0 & 0 & 0 & 0 \end{bmatrix}$$ I see that this answer was obtained by using row 1 - 4 times row 2. Are both of these matrices equal? I thought that there could only be one unique matrix in reduced echelon form.