Solve the System by the Addition Method $$\left\{ \begin{array} { r } 5 x + 6 y = - 7 \\- 5 x - 13 y = 21\end{array} \right.$$

question 9

Multiple Choice

Solve the system by the addition method.
- $$\left\{ \begin{array} { r } 5 x + 6 y = - 7 \\- 5 x - 13 y = 21\end{array} \right.$$

• A) \(\{ ( - 1,2 ) \}\)
• B) \(\{ ( x , y ) \mid 5 x + 6 y = - 7 \}\)
• C) \(\varnothing\)
• D) \(\{ ( 1 , - 2 ) \}\)

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Definitions:

Hagia Sophia

An architectural masterpiece originally built as a Christian cathedral in Constantinople (modern-day Istanbul, Turkey) and later converted into a mosque, now a museum.

Obelisk of Theodosius

An ancient Egyptian obelisk erected at the Hippodrome of Constantinople by the Roman emperor Theodosius I in the 4th century AD.

Hagia Sophia

A historic architectural marvel in Istanbul, Turkey, originally built as a Christian cathedral, then converted into a mosque, and now a museum, exemplifying Byzantine architecture.

Procopius

A Byzantine Greek historian of the 6th century, known for his works "The Wars of Justinian", "The Buildings of Justinian", and the scandalous "Secret History".