Answer
$x=-2$
Work Step by Step
The function is $q(x)=\frac{1}{2}x-3$
Substitute $-4$ for $q(x)$ to get
$-4=\frac{1}{2}x-3$
Add $3$ to both sides of the equation to get
$-4+3=\frac{1}{2}x-3+3$
$\implies -1=\frac{1}{2}x$
Multiply both sides of the equation by $2$.
Then, we have
$-1(2)=(2)\frac{1}{2}x$
$\implies -2=x$
When $x=-2$, $q(x)=-4$
