Solve the System of Equations by the Substitution Method $$\begin{array} { l } x - 7 y = - 40 \\4 x - 8 y = - 20\end{array}$$

Multiple Choice

Solve the system of equations by the substitution method.
- $$\begin{array} { l } x - 7 y = - 40 \\4 x - 8 y = - 20\end{array}$$

A) $\{ ( - 9,8 ) \}$
B) $\{ ( 8,8 ) \}$
C) $\{ ( 9,7 ) \}$
D) $\varnothing$