Recently seen by a colleague as a True/False question in homework, I'd be interested in your answers. Please respond to the poll, express opinions in replies, and boost for reach.
A line is parallel to itself:
@ColinTheMathmoI say "True" provided the definition is the slope is the same. The other concept that the lines don't touch each other is very weak and does not hold true for separate parallel lines in non Euclidean geometries.
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