Use the Gauss-Jordan Method to Solve the System of Equations $$\begin{array} { l } 2 x + 5 y = - 7 \\- 6 x - 15 y = 21\end{array}$$

Multiple Choice

Use the Gauss-Jordan method to solve the system of equations. If the system has infinitely many solutions, give the
solution with y arbitrary.
- $$\begin{array} { l } 2 x + 5 y = - 7 \\- 6 x - 15 y = 21\end{array}$$

A) $\varnothing$
B) $\left\{ \left\{ - \frac { 5 } { 2 } y - \frac { 7 } { 2 } , y \right) \right\}$
C) $\left\{ \left\{ - \frac { 5 } { 2 } y + \frac { 7 } { 2 } , y \right) \right\}$
D) $\{ ( - 1 , - 1 ) \}$