$$\left. \begin{array} { l } { x = 10 } \\ { y = 10 } \\ { y = 10 } \\ { x y = 100 } \\ { a b = 9 } \end{array} \right.$$
$x=10$
$y=10$
$a=\frac{9}{b}\text{ and }b\neq 0$
