Answer
$y-12=-2(x)$
Work Step by Step
RECALL:
(1) The point-slope form of a line's equation is $y-y_1=m(x-x_1)$ where $m$=slope and $(x_1, y_1)$ is a point on the line.
(2) The slope-intercept form of a line is $y=mx+b$ where $m$=slope and $(0, b)$ is the line's y-intercept.
With $m=-2$ and $b=12$, substituting these into the slope-intercept form of a line gives:
$y=-2x+12$
To convert the equation above into point-slope form, subtract 12 to both sides of the equation to obtain:
$y-12 = -2x+12-12
\\y-12=-2(x)$