Which two undefined geometric terms always describe figures with no beginning or end?

Answer:lines, andplanes.Explanation:In geometry, undefined terms refer to three entities: points, lines, and planes. They are considered undefined because they are rather described than formally defined.The reason behind this lack of definition is that they are abstractions: you cannot touch or see a real point, line or plane.A point represents a position in the plane or the space, and it is dimensionless. Yet it is used to define a line and a plane.Among those three terms, only line and plane meet the feature of not having begin or end. That is so because lines  and planes extend infinetly LInes extend in two directions, in one dimension: for example, from left to right, or from east to west, or vertically.Planes extend infinetly in two dimensions: they are flat infinite surfaces.