Question 59473
THE SLOPE OF EQUATION #1 IS 
4X-3Y=36
-3Y=-4X+36
Y=-4X/-3+36
Y=4/3X+36 THEN THE SLOPE=4/3
THE SLOPE OF EQUATION # 2 IS
3X+4Y=20
4Y=-3X+20
Y=-3X/4+20 
Y=-3/4X+20 THEN THE SLOPE=-3/4 
THUS THESE 2 LINES ARE PERPENDICULAR BECAUSE THE SLOPES A NEGATIVE RECIPRICAL OF EACH OTHER.