Solving for y, we can start by expanding to get y-3=5x-20. Next, we can add 3 to both sides (to separate y), resulting in y=5x-17. To find the slope in the equation y=mx+b, you simply find what you multiply x by, which is 5 in this case. To find a perpendicular slope, you start by making the slope (5 in this case) negative. Next, we find the reciprocal of the number. Since -5 can be written as -5/1, the reciprocal and therefore perpendicular slope is -1/5