## Contains The Origin

#### Problem

Two points, A and B, are selected at random on a co-ordinate plane. Lines are drawn through each of the points that are parallel to both the `x` and `y` axes so as to form a rectangular region.

Three points, X, Y, and Z, are selected at random on the same plane so as to form a triangle.

Which shape is most likely to contain the origin?

Problem ID: 237 (02 Aug 2005) Difficulty: 4 Star