Question 79480
Find the slope of any line perpendicular to the line through points (0, 5) and (-3, -4).

1- The formula for slope is y2-y1/x2-x1.
   Let y2=-4, y1=5, x2=-3, x1=0
   -4-5/-3-0
   -9/-3
    3
2- The slope of the line is 3. The slopes of perpendicular lines are negative reciprocals of each other. The slope of any line perpendicular to this line would be -1/3.

3- Why is the slope of the perpendicular line -1/3? The reciprocal of 3 is 1/3. To find the negative reciprocal, change the sign.