[math]\large\begin{array}{ccc}[br]\textcolor{red}{row}&\textcolor{red}\text{second row}\textcolor{red}\downarrow&\\[br]\textcolor{red}{first}&\left(\left(\begin{array}{c}1\\0\\0\\\end{array}\right) \; \left(\begin{array}{rrr}0&-1&0\\\end{array}\right) \right)+ Identity \left(3 \right) & \\[br]\textcolor{red}\text{add to}\textcolor{red}\uparrow &\textcolor{red}\leftarrow\textcolor{red}\text{multiplied by \minus1}&\\\end{array}[/math]