Here m' is the slope of the perpendicular.
The equation is where
First of all find the slope of your line given by the equation x - 8y = 2. Let's put it in slope-intercept form:
So the slope is
The slope of a line perpendicular to this line would be the negative reciprocal of , or .
Using the point (-8, 9) and a slope of -8, we can now find the y-intercept.
Substituting back into the slope intercept form, we arrive at: