Your friend drew the diagram below to prove to you that two planes can intersect in exactly one point. Describe your friend's error.

A plane extends infinitely in two-dimension and it does not have a boundary

The error is in designating rectangles which are bounded planar shape as an whole plane

The reason for the error stated above is as follows:

Missing part of question: The drawing of the question that appear missing is attached

The definition of a plane in mathematics is an infinitely long and wide two-dimensional surface that has no thickness and which is defined by either;

The given figure is the diagram of two rectangles which are planar shapes enclosed by four straight line boundaries each of which are located in their respective planes that extends infinitely and are not entire planes by themselves

Therefore, the error is that a bounded planar figure is taken as being an infinite plane

Learn more about dots, lines, and planes here:

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