Checking to see if 3 points are on the same line

Question

I want to know a piece of a code which can actually tell me if 3 points in a 2D space are on the same line or not. A pseudo-code is also sufficient but Python is better.

Answer 1

Read this, and use it to find the equation of a line through the first two points. Follow the instructions to find m and b. Then for your third point, calculate mx + b - y. If the result is zero, the third point is on the same line as the first two.