Solve the System by the Addition Method $$\begin{aligned}x - 4 y & = - 15 \\8 x - 5 y & = 42\end{aligned}$$

question 115

Multiple Choice

Solve the system by the addition method.
- $$\begin{aligned}x - 4 y & = - 15 \\8 x - 5 y & = 42\end{aligned}$$

• A) \(\{ ( 9,6 ) \}\)
• B) \(\{ ( - 9,7 ) \}\)
• C) \(\{ ( 8,7 ) \}\)
• D) \(\varnothing\)

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