## Algebra and Trigonometry 10th Edition

$x=3; y=-2$
The general form of a matrix of order $2 \times 2$ is: $det \ A=\begin{vmatrix} p & q \\ r & s\end{vmatrix}=ps-qr$ Now, $|A|=\begin{vmatrix} 3 & 8 \\ 9 & -5 \end{vmatrix}=-87$ Since the determinant is not zero, we will use Cramers Rule. $x=\dfrac{\begin{vmatrix} -7 & 8 \\37 & -5 \end{vmatrix}}{-87}=\dfrac{-261}{-87}=3$ and $y=\dfrac{\begin{vmatrix} 3 & -7 \\9& 37 \end{vmatrix}}{-87}=\dfrac{174}{-87}=-2$ So, $x=3; y=-2$