First, let us solve for the slope of the line which it intersects with:
m’ = (y2 – y1) / (x2 – x1)
m’ = (-3 – 4) / (-2 – 5)
m’ = 1
The slope of the perpendicular line is the negative reciprocal, therefore:
m = - 1 / m’
m = - 1 / 1
m = -1
So the slope of the line is -1.