Use Back-Substitution to Solve the System of Linear Equations $$\left\{ \begin{array} { r } - x + 7 y - 5 z = 51 \\5 y - 8 z = 82 \\z = - 9\end{array} \right.$$

question 72

Multiple Choice

Use back-substitution to solve the system of linear equations. $$\left\{ \begin{array} { r } - x + 7 y - 5 z = 51 \\5 y - 8 z = 82 \\z = - 9\end{array} \right.$$

• A) \(( 2,8 , - 9 )\)
• B) \(( 8,2 , - 9 )\)
• C) \(( 8 , - 9,2 )\)
• D) \(( - 9,2,8 )\)
• E) \(( 0,2 , - 9 )\)

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