Solve the System by Graphing $\left\{\begin{array}{l}x=-y \\y+x=6\end{array}\right.$ A) $\{ ( 1,5 ) \}$

Multiple Choice

Solve the system by graphing. If there is no solution or an infinite number of solutions, so state. Use set notation to
express the solution set.
- $\left\{\begin{array}{l}x=-y \\y+x=6\end{array}\right.$

A) $\{ ( 1,5 ) \}$
B) $\{ ( 1,1 ) \}$
C) no solution; $\varnothing$
D) infinitely many solutions; $\{ ( x , y ) \mid y + x = 6 \}$ or $\{ ( x , y ) \mid x = - y \}$