Fill in the Blank Using Elementary Row Operations to Form $$\left[ \begin{array} { r r r } 2 & 1 & - 2 \\- 10 & - 1 & 9\end{array} \right]$$

Multiple Choice

Fill in the blank using elementary row operations to form a row-equivalent matrix. $$\left[ \begin{array} { r r r } 2 & 1 & - 2 \\- 10 & - 1 & 9\end{array} \right]$$ $$\left[ \begin{array} { l l l } 2 & 1 & - 2 \\0 & \square & - 1\end{array} \right]$$

A) $$\left[ \begin{array} { c c c } 2 & 1 & - 2 \\0 & - 6 & - 1\end{array} \right]$$
B) $$\left[ \begin{array} { l l l } 2 & 1 & - 2 \\0 & 4 & - 1\end{array} \right]$$
C) $$\left[ \begin{array} { r r r } 2 & 1 & - 2 \\0 & - 4 & - 1\end{array} \right]$$
D) $$\left[ \begin{array} { l l l } 2 & 1 & - 2 \\0 & 1 & - 1\end{array} \right]$$ ​
E) $$\left[ \begin{array} { l l l } 2 & 1 & - 2 \\0 & 0 & - 1\end{array} \right]$$ ​