Without Graphing, Decide:
(A)Are the Graphs of the Equations Are $\left\{ \begin{aligned}x & = - y \\y + x & = 5\end{aligned} \right.$

Multiple Choice

Without graphing, decide:
(a) Are the graphs of the equations are identical lines, parallel lines, or lines intersecting at a single point?
(b) How many solutions does the system have?
- $\left\{ \begin{aligned}x & = - y \\y + x & = 5\end{aligned} \right.$

A) parallel lines; no solution
B) identical lines; infinite number of solutions
C) lines intersecting at a single point; one solution