What you need to do first is to get the midpoint and slope of the line segment.
A(-2,5) and B(4,3)
The midpoint formula is:
x=(x1+x2)/2, y=(y1+y2)/2
x=(-2+4)/2 = 1
y=(5+3)/2 = 4
The midpoint is at (1,4).
Next, the slope (m).
m=(y2 - y1)/(x2 - x1)
m=(3-5)/(4+2) = -2/6 = -1/3
A perpendicular bisector passes through the midpoint and form a right angle. Two lines form a right angle when their slopes are negative reciprocals:
Calculated m =-1/3
Negative reciprocal of m = 3
Let's use the point slope form of linear equation:
y - y1 = m (x - x1)
Therefore, the equation (l) is:
y - 4 = 3(x - 1)