Solve the System by the Method of Your Choice $$\begin{array} { l } x + y = - 9 \\x - y = 12\end{array}$$

question 229

Multiple Choice

Solve the system by the method of your choice. Identify systems with no solution and systems with infinitely many
solutions, using set notation to express their solution sets.
- $$\begin{array} { l } x + y = - 9 \\x - y = 12\end{array}$$

• A) \(\{ ( 1.5 , - 10.5 ) \}\)
• B) \(\{ ( 1.5,10.5 ) \}\)
• C) \(\{ ( x , y ) \mid x + y = - 9 \}\)
• D) \(\varnothing\)