Answer
a) $a=5;b=10$
b) $a=-2; b=9$
Work Step by Step
$$ax=b-5$$
We can only use values $-2,5,9,10$ for $a$ and $b$.
$a)$
When $\boxed{a=5}$ and $\boxed{b=10}$, $x$ will be positive integer:
$$5x=10-5$$
$$5x=5$$
$$x=1$$
$b)$
When $\boxed{a=-2}$ and $\boxed{b=9}$, $x$ will be negative integer:
$$-2x=9-5$$
$$-2x=4$$
$$x=-2$$
