Solve the System Using the Inverse That Is Given for the Coefficient

question 75

Multiple Choice

Solve the system using the inverse that is given for the coefficient matrix.
- $x + 2 y + 3 z = - 10$ $x + y + z = - 7$ $- x + y + 2 z = - 4$$\quad$ The inverse of $\left[ \begin{array} { r r r } 1 & 2 & 3 \\ 1 & 1 & 1 \\ - 1 & 1 & 2 \end{array} \right]$ is $\left[ \begin{array} { r r r } 1 & - 1 & - 1 \\ - 3 & 5 & 2 \\ 2 & - 3 & - 1 \end{array} \right]$

• A) \(\{ ( 1 , - 13,5 ) \}\)
• B) \(\{ ( 3 , - 13,0 ) \}\)
• C) \(\{ ( - 10 , - 28,8 ) \}\)
• D) \(\{ ( - 21 , - 73 , - 45 ) \}\)

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Profit Margin

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