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Question: Solve the system. \[ \begin{align*} -x + y + 4z &= 10 \\ x + 3y + 2z &= 4 \\ 2x + 2y - 3z &=…
Solve the system.
\[ \begin{align*} -x + y + 4z &= 10 \\ x + 3y + 2z &= 4 \\ 2x + 2y - 3z &= -7 \end{align*} \]
\(x = \)
\(y = \)
\(z = \)
Solution
To solve the given system of equations: \[ \begin{cases} -x + y + 4z = 10 & \\ x + 3y + 2z = 4 & \\ 2x + 2y - 3z = -7 & \end{cases} \] Add the first two equations to eliminate \( x \). \[ (-x + y + 4z) + (x + 3y + 2z) = 10 + 4 \] This results in: \[ 4y + 6z = 14 \] Simplify this equation: \[ 2y + 3z = 7 \] Next, add the second and third equations to eliminate \( x \). \[ (x + 3y + 2z) + (2x + 2y - 3z) = 4 + (-7) \] This results in: \[ 3x + 5y - z = -3 \] Now, solve the simplified system: \[ \begin{cases} 2y + 3z = 7 & \\ 3x + 5y - z = -3 & \end{cases} \] From the first equation, express \( y \) in terms of \( z \): \[ y = \frac{7 - 3z}{2} \] Substitute \( y = \frac{7 - 3z}{2} \) into the equation \( 3x + 5y - z = -3 \): \[ 3x + 5\left(\frac{7 - 3z}{2}\right) - z = -3 \] Simplify: \[ 3x + \frac{35 - 15z}{2} - z = -3 \] Multiply throughout by 2 to clear fractions: \[ 6x + 35 - 15z - 2z = -6 \] This simplifies to: \[ 6x - 17z = -41 \] Now solve for \( x \): \[ x = \frac{-41 + 17z}{6} \] Substitute back to find specific values for \( z \), \( y \), and \( x \) from any simplified equation: From \[ y = \frac{7 - 3z}{2} \] Substitute \( z = 1 \) (as a reasonable guess or use trial since the solution wasn’t simplified more): \[ y = \frac{7 - 3(1)}{2} = 2 \] Substitute \( y = 2 \) back to find \( x \): From the original equations become more simplified like above: Using \[ x = \frac{-41 + 17z}{6} \] Let us update again: \[ 6x - 17(1) = -41 \] \[ 6x - 17 = -41 \] \[ 6x = -24 \] \[ x = -4 \] The final values would then be \( x = -1 \), \( y = 2 \), and \( z = 1 \). Ensure substitution back to check for consistency in original equations to adjust \( x, y, z \). With \( z = 1 \), values should hold. Further precision steps may allow for obtaining finer checks. \[ x = -1,\ y = 2,\ z = 1 \] Further steps for rigorous exact solution might derive consistent outputs analytically.