Perform the indicated elementary row operations.
-$\begin{array} { l }
\mathrm { R } _ { 1 } + \mathrm { R } _ { 2 } \
{ \left[ \begin{array} { r r }
9 & 1 \
8 & - 2
\end{array} \right] }
\end{array}$

A)$\left[\begin{array}{rr}
17 & -1 \
8 & -2
\end{array}\right]$

B)$\left[\begin{array}{rr}
9 & 1 \
17 & -1
\end{array}\right]$

C)$\left[\begin{array}{rr}
9 & 10 \
8 & 6
\end{array}\right]$

D)$\left[\begin{array}{ll}
17 & -1 \
17 & -1
\end{array}\right]$

Question

Perform the indicated elementary row operations.
-$\begin{array} { l } 
\mathrm { R } _ { 1 } + \mathrm { R } _ { 2 } \
{ \left[ \begin{array} { r r } 
9 & 1 \
8 & - 2
\end{array} \right] }
\end{array}$

A)$\left[\begin{array}{rr}
17 & -1 \
8 & -2
\end{array}\right]$

B)$\left[\begin{array}{rr}
9 & 1 \
17 & -1
\end{array}\right]$

C)$\left[\begin{array}{rr}
9 & 10 \
8 & 6
\end{array}\right]$

D)$\left[\begin{array}{ll}
17 & -1 \
17 & -1
\end{array}\right]$

Quizplus · Accepted Answer

Adding $R_1$ to $R_2$ means adding the elements of the first row to the corresponding elements of the second row. The operation is performed only on $R_2$, so the first row remains unchanged. $9+8=17$ and $1+(-2)=-1$, so the new $R_2$ is $[17\ -1]$.

Perform the Indicated Elementary Row Operations A) [17−18−2]\left[\begin{array}{rr}17 & -1 \\8 & -2\end{array}\right][178​−1−2​]

Perform the Indicated Elementary Row Operations A) $\left[\begin{array}{rr}17 & -1 \\8 & -2\end{array}\right]$