Solution:
Let us denote by L1 the line given by the following equation:

solving for 3y, this equation is equivalent to:

that is:

now, solving for y, we obtain:

that is:

now, perpendicular lines have opposite-reciprocal slopes, so the slope of the line we want to find is

with this information, we can say that the provisional slope-intercept form of the perpendicular line to L1 is:

our goal is now to find the y-intercept b of this line. To do this, we can replace the point (x,y)=(8, -8) into the previous equation, to get:

solving for b, we get:

so that, we can conclude that the equation of the line would be:
