Axioms:A1: There is at least one pointA2: Every point is on exactly two linesA3: Every line is on exactly three pointsExplore the geometry with sketching and models. Check to see which models are isomorphic and which are not.

Axioms:A1: There is at least one pointA2: Every point is on exactly two linesA3: Every line is on exactly three pointsExplore the geometry with sketching and models. Check to see which models are isomorphic and which are not.

Axioms: A1: There is at least one point A2: Every point is on exactly two lines A3: Every line is on exactly three points Explore the geometry with sketching and models. Check to see which models are isomorphic and which are not.