Im trying to get the determinant of \begin{vmatrix} 2 & 3 & 2x & -1 \\ 2 & x+3 & 2x & -1 \\ 2 -x & 3 &3x &0 \\ 0 & 3 & 2x+2 &x-1 \end{vmatrix}
And they show that they go from the above matrix to this:
\begin{vmatrix} 2(x+1) & 3 & 2x & -1 \\ 2(x+1) & x+3 & 2x & -1\\ 2(x+1) & 3 & 3x & 0 \\ 2(x+1) & 3 & 2x+2 & x-1 \end{vmatrix}
I do not quite follow how these two steps are connected.