Solve the System by Substitution $$\begin{array} { l } x + y = - 6 \\x - y = - 4\end{array}$$

Multiple Choice

Solve the system by substitution.
- $$\begin{array} { l } x + y = - 6 \\x - y = - 4\end{array}$$

A) $\{ ( - 5 , - 1 ) \}$
B) $\varnothing$
C) $\{ ( 5,0 ) \}$
D) $\{ ( - 6,0 ) \}$