Find the System of Linear Equations Represented by the Augmented $$\left[ \begin{array} { c c c c } 1 & 7 & \vdots & 0 \\0 & 1 & \vdots & - 1\end{array} \right]$$

Multiple Choice

Find the system of linear equations represented by the augmented matrix.Then use back substitution to solve.(Use variables x,y,z,and w if applicable. ) ​ $$\left[ \begin{array} { c c c c } 1 & 7 & \vdots & 0 \\0 & 1 & \vdots & - 1\end{array} \right]$$ ​

A) ​ $$\left\{ \begin{array} { r } x + 7 y = 0 \\y = 0\end{array} \right.$$ ​​(7,0)
B) ​ $$\left\{ \begin{aligned}x + 7 y & = 0 \\x & = - 1\end{aligned} \right.$$ ​​(-1,7)
C) ​ $$\left\{ \begin{aligned}x + 7 y & = 0 \\y & = - 1\end{aligned} \right.$$ ​​(7,-1)
D) ​ $$\left\{ \begin{array} { r } x + 7 y = 0 \\y = 1\end{array} \right.$$ ​​(7,1)
E) ​ $$\left\{ \begin{aligned}x + 7 y & = 0 \\y & = - 1\end{aligned} \right.$$ ​​​(7,1)