We are asked to examine the following statement to determine if it is always, sometimes, or never true.
Two planes intersect at a point.
According to Postulate 2.7, if two planes intersect then their intersection is a line.
According to Postulate 2.3, this intersection line contains at least two points.
Thus, the intersection of two planes always contains at least two points. Two planes never intersect at exactly one point.
