1. **State the problem:** Solve the system of equations using Cramer's rule:
$$3x - 2y = 4$$
$$2x + y = 7$$
2. **Recall Cramer's rule:** For a system
$$a_1x + b_1y = c_1$$
$$a_2x + b_2y = c_2$$
The solutions are given by:
$$x = \frac{\begin{vmatrix} c_1 & b_1 \\ c_2 & b_2 \end{vmatrix}}{\begin{vmatrix} a_1 & b_1 \\ a_2 & b_2 \end{vmatrix}}, \quad y = \frac{\begin{vmatrix} a_1 & c_1 \\ a_2 & c_2 \end{vmatrix}}{\begin{vmatrix} a_1 & b_1 \\ a_2 & b_2 \end{vmatrix}}$$
3. **Identify coefficients:**
$$a_1 = 3, b_1 = -2, c_1 = 4$$
$$a_2 = 2, b_2 = 1, c_2 = 7$$
4. **Calculate the determinant of the coefficient matrix:**
$$D = \begin{vmatrix} 3 & -2 \\ 2 & 1 \end{vmatrix} = (3)(1) - (-2)(2) = 3 + 4 = 7$$
5. **Calculate determinant for $x$:**
$$D_x = \begin{vmatrix} 4 & -2 \\ 7 & 1 \end{vmatrix} = (4)(1) - (-2)(7) = 4 + 14 = 18$$
6. **Calculate determinant for $y$:**
$$D_y = \begin{vmatrix} 3 & 4 \\ 2 & 7 \end{vmatrix} = (3)(7) - (4)(2) = 21 - 8 = 13$$
7. **Find $x$ and $y$:**
$$x = \frac{D_x}{D} = \frac{18}{7}$$
$$y = \frac{D_y}{D} = \frac{13}{7}$$
**Final answer:**
$$x = \frac{18}{7}, \quad y = \frac{13}{7}$$
Cramers Rule 28D24D
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