Answer:
m = -1/3
Step-by-step explanation:
The slope of the line can be calculated using the slope formula.
[tex]m = \frac{y_2-y_1}{x_2-x_1} = \frac{9--3}{4-0} = \frac{12}{4} = 3[/tex]
Since this is the line with points AB, the slope of any line perpendicular to it will be -1/3. All perpendicular lines cross at a 90 degree angle and as such their slopes are the negative reciprocals of each other. This means 3 becomes -1/3.
