In the Euclidean plane, precisely one line through a point outside a given line is parallel to it. This formulation is equivalent to Euclid's fifth postulate within the usual axioms of plane geometry.
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The Parallel Postulate, also known as Euclid's Fifth Postulate, is a fundamental principle in Euclidean geometry. It states that given a line and a point not on that line, there is exactly one line through the point that is parallel to the given line.
