Line segment RS is perpendicular to line segment PQ, and the coordinates are R(4, -5), S(-8, 4), P(0, 6), and Q(-3, y). What is the value of y?

Answer 1

First RS
slope = (4 - -5) / (-8 - 4)
= 9/-12 = -3/4
so it is
y = -(3/4) x + b
no need to find b, all we need is the slope -3/4
so
slope of perpendicular = -1/m = +4/3
so
4/3 = (y-6) /( -3 - 0)
4/3 = (y-6)/-3
-4 = y-6
y = 2