Answer
$x=2$
Work Step by Step
In order to determine $x$, we have to compute the determinants $D,D_x$:
$D=\begin{vmatrix}3&1&-2\\2&7&3\\4&-3&-1\end{vmatrix}=-21+12+12+56+27+2=88$
$D_x=\begin{vmatrix}-3&1&-2\\9&7&3\\7&-3&-1\end{vmatrix}=21+21+54+98-27+9=176$
We use Cramer's Rule to determine $x$:
$x=\dfrac{D_x}{D}=\dfrac{176}{88}=2$
