Answer
$y+8=-2(x-3)$
Work Step by Step
The point-slope form of an equation of a non-vertical line with slope $m$ through the point $(x_1,y_1)$ is $y-y_1=m(x-x_1)$.
We plug in $3$ for $x_1$, $-8$ for $y_1$, and $-2$ for $m$ to get the equation:
$y-(-8)=-2(x-3)$
We simplify: $y+8=-2(x-3)$