Use Inverses to Solve Matrix Equations
- $$\begin{array} { r } 5 x + 7 z = 83 \\9 y + 6 z = 72 \\4 x + 7 y - 2 z = 12\end{array}$$

question 120

Multiple Choice

Use Inverses to Solve Matrix Equations
- $$\begin{array} { r } 5 x + 7 z = 83 \\9 y + 6 z = 72 \\4 x + 7 y - 2 z = 12\end{array}$$

• A) \(\left[ \begin{array} { r r r } 5 & 0 & 7 \\ 0 & 9 & 6 \\ 4 & 7 & - 2 \end{array} \right] \left[ \begin{array} { l } x \\ y \\ z \end{array} \right] = \left[ \begin{array} { l } 83 \\ 72 \\ 12 \end{array} \right]\)
• B)
• \[\left[ \begin{array} { r r r }
• 5 & 0 & 4 \\
• 0 & 9 & 7 \\
• 7 & 6 & - 2
• \end{array} \right] \left[ \begin{array} { l }
• x \\
• y \\
• z
• \end{array} \right] = \left[ \begin{array} { l }
• 83 \\
• 72 \\
• 12
• \end{array} \right]\]
• C)
• \[\left[ \begin{array} { r r r }
• 5 & 7 & 0 \\
• 9 & 6 & 0 \\
• 4 & 7 & - 2
• \end{array} \right] \left[ \begin{array} { l }
• x \\
• y \\
• z
• \end{array} \right] = \left[ \begin{array} { c }
• 83 \\
• 72 \\
• 12
• \end{array} \right]\]
• D)
• \[\left[ \begin{array} { l l }
• 5 & 0 \\
• 0 & 9 \\
• 4 & 7
• \end{array} \right] \left[ \begin{array} { l }
• x \\
• y \\
• z
• \end{array} \right] = \left[ \begin{array} { l }
• 7 \\
• 6 \\
• - 2
• \end{array} \right]\]

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