Question

If the line segment connecting point P (5,2) to point R (3,6) is rotated 90 degrees counter clockwise about point R what is the slope of the original segment PR?

Answer 1

Given:
P (5, 2) 
R (3, 6)

finding the slope of a straight line.

m = y1 - y2 / x1-x2 = (2-6) / (5-3) = -4 / 2 = -2

The slope of the original segment PR is -2. 

I graphed the changes. The new coordinate of P is (7,8)