how to find the slope of a line parallel and perpendicular?
To find the slope of this line we need to get the line into slope-intercept form (y = mx + b), which means we need to solve for y: The slope of the line 4x – 5y = 12 is m = 4/5. Therefore, the slope of every line parallel to this line would have to be m = 4/5. Two lines are perpendicular if .