OJ Board

EDIT: I got an AC on mine... A few pointers though:
1. Use fabs... And not -h
2. No need to make it x^2 rather than (x + 0.000)^2
3. Division by zero can be avoided if you don't find slope.

Aim is to find equation: ax + by + c = 0
Slope:
m = (y2 - y1)/(x2 - x1)
also m = -a/b
take a = y1 - y2
and ...