我看了您的鏈接，還有一個問題。
Given points are,
A = (3, 2),
B = (1, 4),
C = (5, 4)
To find out the circumcenter we have to solve any two bisector equations and find out the intersection points.
So, mid point of AB = [(3 + 1)/2, (2 + 4)/2] = (2, 3)
Slope of AB = [(4−2)/(1−3)] = -1
請問Slope of AB 為什麽是B-A，不是A-B呢？
