1 answer
(click or scroll down)
The original line is in slope-intercept form, y = mx + b, where m is the slope.
The given equation, y = (1/3)x - 5, has a slope of 1/3.
A line perpendicular to this line will have a slope that is the negative reciprocal of 1/3.
The negative reciprocal of 1/3 is -3.
Therefore, the slope of a line perpendicular to y = (1/3)x - 5 is -3.