Use Back-Substitution to Solve the System of Linear Equations $$\left\{ \begin{array} { c l } 2 x - y + 5 z & = 24 \\y + 2 z & = 9 \\z & = 7\end{array} \right.$$

Multiple Choice

Use back-substitution to solve the system of linear equations. $$\left\{ \begin{array} { c l } 2 x - y + 5 z & = 24 \\y + 2 z & = 9 \\z & = 7\end{array} \right.$$

A) $( - 8 , - 5,7 )$
B) $( - 8,5,7 )$
C) $( - 8 , - 5 , - 7 )$
D) $( - 7 , - 5,7 )$
E) $( - 8 , - 5 , - 5 )$