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If the system of linear equations x+ky+3...

If the system of linear equations `x+ky+3z=0, 3x+ky-2z=0, 2x+4y-3z=0` has a non-zero solution `(x,y,z)` then `(xz)/(y^2)` is equal to

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To solve the system of linear equations given by: 1. \( x + ky + 3z = 0 \) 2. \( 3x + ky - 2z = 0 \) 3. \( 2x + 4y - 3z = 0 \) we need to find the value of \( \frac{xz}{y^2} \) when there is a non-zero solution for \( (x, y, z) \). ### Step 1: Formulate the system in matrix form We can express the system of equations in matrix form as follows: \[ \begin{bmatrix} 1 & k & 3 \\ 3 & k & -2 \\ 2 & 4 & -3 \end{bmatrix} \begin{bmatrix} x \\ y \\ z \end{bmatrix} = \begin{bmatrix} 0 \\ 0 \\ 0 \end{bmatrix} \] ### Step 2: Calculate the determinant For the system to have a non-zero solution, the determinant of the coefficient matrix must be zero: \[ \Delta = \begin{vmatrix} 1 & k & 3 \\ 3 & k & -2 \\ 2 & 4 & -3 \end{vmatrix} \] Calculating the determinant: \[ \Delta = 1 \begin{vmatrix} k & -2 \\ 4 & -3 \end{vmatrix} - k \begin{vmatrix} 3 & -2 \\ 2 & -3 \end{vmatrix} + 3 \begin{vmatrix} 3 & k \\ 2 & 4 \end{vmatrix} \] Calculating the minors: 1. \( \begin{vmatrix} k & -2 \\ 4 & -3 \end{vmatrix} = k(-3) - (-2)(4) = -3k + 8 \) 2. \( \begin{vmatrix} 3 & -2 \\ 2 & -3 \end{vmatrix} = 3(-3) - (-2)(2) = -9 + 4 = -5 \) 3. \( \begin{vmatrix} 3 & k \\ 2 & 4 \end{vmatrix} = 3(4) - k(2) = 12 - 2k \) Putting it all together: \[ \Delta = 1(-3k + 8) - k(-5) + 3(12 - 2k) \] \[ = -3k + 8 + 5k + 36 - 6k \] \[ = (-3k + 5k - 6k) + (8 + 36) = -4k + 44 \] Setting the determinant to zero for a non-zero solution: \[ -4k + 44 = 0 \implies 4k = 44 \implies k = 11 \] ### Step 3: Substitute \( k \) back into the equations Now substituting \( k = 11 \) into the original equations: 1. \( x + 11y + 3z = 0 \) 2. \( 3x + 11y - 2z = 0 \) 3. \( 2x + 4y - 3z = 0 \) ### Step 4: Solve the equations From the first equation: \[ z = -\frac{x + 11y}{3} \] Substituting \( z \) into the second equation: \[ 3x + 11y - 2\left(-\frac{x + 11y}{3}\right) = 0 \] \[ 3x + 11y + \frac{2x + 22y}{3} = 0 \] Multiplying through by 3 to eliminate the fraction: \[ 9x + 33y + 2x + 22y = 0 \implies 11x + 55y = 0 \implies x = -5y \] Now substituting \( x = -5y \) into the expression for \( z \): \[ z = -\frac{-5y + 11y}{3} = -\frac{6y}{3} = -2y \] ### Step 5: Calculate \( \frac{xz}{y^2} \) Now we have: - \( x = -5y \) - \( z = -2y \) Calculating \( \frac{xz}{y^2} \): \[ \frac{xz}{y^2} = \frac{(-5y)(-2y)}{y^2} = \frac{10y^2}{y^2} = 10 \] ### Final Answer Thus, the value of \( \frac{xz}{y^2} \) is: \[ \boxed{10} \]

To solve the system of linear equations given by: 1. \( x + ky + 3z = 0 \) 2. \( 3x + ky - 2z = 0 \) 3. \( 2x + 4y - 3z = 0 \) we need to find the value of \( \frac{xz}{y^2} \) when there is a non-zero solution for \( (x, y, z) \). ...
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