Prove that points A (-3,-1) , B (6,5) , C ( 3,3) are collinear .From textbook

Answer 1

I will not solve this for you, but I will tell you how to do it.

Find the equation of the straight line through any 2 of the points, using the point slope form.

Then, see if the remaining point satisfies that equation. If so, then the points are co-linear.