Write the System of Linear Equations Represented by the Augmented $x , y , z$

question 19

Multiple Choice

Write the system of linear equations represented by the augmented matrix. (Use variables $x , y , z$ , and $w$ .)
$\left[ \begin{array} { c c c c : c } - 4 & 0 & 0 & - 9 & - 9 \\ 7 & - 8 & 0 & 0 & 1 \\ 0 & - 4 & - 7 & - 9 & - 8 \\ 0 & 0 & - 4 & 1 & - 8 \end{array} \right]$

• A)
• \(\left\{ \begin{aligned} - 4 x - 9 y & = - 9 \\ 7 x - 8 y & = 1 \\ - 4 x - 7 y - 9 z & = - 8 \\ - 4 x + y & = - 8 \end{aligned} \right.\)
• B)
• \(\left\{ \begin{aligned} - 4 x - 9 z & = - 9 \\ 7 x - 8 y & = 1 \\ - 4 y - - 7 z - 9 w & = - 8 \\ - 4 z + w & = - 8 \end{aligned} \right.\)
• C)
• \(\left\{ \begin{array} { r l r } - 4 x & - 9 z & = - 9 \\ 7 x & - 8 z & = 1 \\ - 4 y - 7 z - 9 w & = - 8 \\ - 4 z + w & = - 8 \end{array} \right.\)
• D)
• \(\left\{\begin{array}{lr}
• -4 x& -9 w=-9\\
• 7 x-8 y & \quad=1\\
• \quad -4 y-7 z & -9 w=-8\\
• \quad -4 y+z & \quad=-8
• \end{array}\right.\)
• E)
• \(\left\{\begin{array}{lr}
• -4 x& -9 w=-9\\
• 7 x-8 y & \quad=1\\
• \quad -4 y-7 z & -9 w=-8\\
• \quad -4 y+z & =-8
• \end{array}\right.\)

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