Writing a equation and making a graph

Twenty-five percent of the customers entering a grocery store between 5 p.m. and 7 p.m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

Of four points are collinear, they are also coplanar

Write the point-slope form of the line passing through (2, -12) and parallel to y=3x.