Write the Word or Phrase That Best Completes Each Statement $\mathrm{R}_{3}=4 \mathrm{r}_{1}+\mathrm{r}_{3}$

Essay

Write the word or phrase that best completes each statement or answers the question.
- $\mathrm{R}_{3}=4 \mathrm{r}_{1}+\mathrm{r}_{3}$

$$\begin{array} { l } \\{ \left[ \begin{array} { r r r | r } - 7 & - 5 & - 1 & - 10 \\6 & - 2 & 9 & 5 \\28 & - 6 & 6 & 18\end{array} \right] }\end{array}$$