A = (-1, 4)
B = (-2, 5)
e: (y(B) - y(A)) * x - (x(B) - x(A)) * y = 0.0
f: (y(B) - y(A)) * (x - x(A)) - (x(B) - x(A)) * (y - y(A)) = 0.0
g: (y(B) - y(A)) * x - (x(B) - x(A)) * y = x(A) * y(B) - x(B) * y(A)