Use Matrices to Solve the System of Equations (If Possible) $$\left\{ \begin{aligned}4 x - 9 y - 9 z & = - 74 \\6 x + 8 y - 2 z & = - 22 \\6 x - y + 9 z & = 4\end{aligned} \right.$$

question 117

Multiple Choice

Use matrices to solve the system of equations (if possible) .Use Gaussian elimination with back-substitution or Gauss-Jordan elimination. $$\left\{ \begin{aligned}4 x - 9 y - 9 z & = - 74 \\6 x + 8 y - 2 z & = - 22 \\6 x - y + 9 z & = 4\end{aligned} \right.$$

• A)x = 5, y = -2, z = 4
• B)x = 2, y = 5, z = -4
• C)x = -5, y = -2, z = 4
• D)no solution
• E)x = -5, y = 2, z = 4

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