In my textbook it says that if you multiply a row in a matrix $A$ by a nonzero constant $c$ to obtain $B$, then $\det{B}=c\det{A}$.
Later on it says that if you obtain $B = cA$ by adding $c$ times the $k^{\text{th}}$ row of $A$ to the $j^{\text{th}}$ row, $\det{B}=\det{A}$.
Isn't this a contradiction though? Is not adding $c$ times the $k^{\text{th}}$ row of $A$ to the $j^{\text{th}}$ row equivalent to multiplying the $k^{\text{th}}$ row by $c$, which increases the determinant by a factor of $c$, and then adding the row down?
In other words, is (I) the same as the (II) with the $2$ steps combined?
I. $cR_k + R_j \rightarrow R_j$. $1$ step in total.
II. First, do $cR_k \rightarrow R_k$. Second, do $cR_k + R_j \rightarrow R_j$. $2$ steps in total.