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With the help of determinants , solve th...

With the help of determinants , solve the following systems of equations :
`2x+3y=9`, `3x-2y=7`

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To solve the system of equations using determinants, we will follow the steps outlined below: ### Given Equations: 1. \( 2x + 3y = 9 \) (Equation 1) 2. \( 3x - 2y = 7 \) (Equation 2) ### Step 1: Write the equations in the form of \( Ax = B \) We can express the system of equations in matrix form \( Ax = B \), where: - \( A \) is the coefficient matrix, - \( x \) is the variable matrix, - \( B \) is the constant matrix. Here, we have: \[ A = \begin{pmatrix} 2 & 3 \\ 3 & -2 \end{pmatrix}, \quad x = \begin{pmatrix} x \\ y \end{pmatrix}, \quad B = \begin{pmatrix} 9 \\ 7 \end{pmatrix} \] ### Step 2: Calculate the determinant \( \Delta \) of matrix \( A \) The determinant \( \Delta \) is calculated as follows: \[ \Delta = \begin{vmatrix} 2 & 3 \\ 3 & -2 \end{vmatrix} = (2 \cdot -2) - (3 \cdot 3) = -4 - 9 = -13 \] ### Step 3: Calculate \( \Delta_x \) (determinant when replacing the first column with \( B \)) To find \( \Delta_x \), we replace the first column of \( A \) with the matrix \( B \): \[ \Delta_x = \begin{vmatrix} 9 & 3 \\ 7 & -2 \end{vmatrix} = (9 \cdot -2) - (3 \cdot 7) = -18 - 21 = -39 \] ### Step 4: Calculate \( \Delta_y \) (determinant when replacing the second column with \( B \)) To find \( \Delta_y \), we replace the second column of \( A \) with the matrix \( B \): \[ \Delta_y = \begin{vmatrix} 2 & 9 \\ 3 & 7 \end{vmatrix} = (2 \cdot 7) - (9 \cdot 3) = 14 - 27 = -13 \] ### Step 5: Calculate \( x \) and \( y \) using Cramer’s Rule Using Cramer’s Rule, we can find \( x \) and \( y \) as follows: \[ x = \frac{\Delta_x}{\Delta} = \frac{-39}{-13} = 3 \] \[ y = \frac{\Delta_y}{\Delta} = \frac{-13}{-13} = 1 \] ### Final Solution: The solution to the system of equations is: \[ x = 3, \quad y = 1 \]
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