Solve the System of Equations by the Addition Method $\left\{ \begin{array} { l } x + y = 0 \\x - y = 14\end{array} \right.$

question 19

Multiple Choice

Solve the system of equations by the addition method.
- $\left\{ \begin{array} { l } x + y = 0 \\x - y = 14\end{array} \right.$

• A) \(( 6 , - 6 )\)
• B) no solution
• C) \(( - 7 , - 6 )\)
• D) \(( 7 , - 7 )\)

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