Question

True or False? (State 'true' or 'false' and add a sentence of brief explanation.

*An angle is defined as the space between two rays that emanate from a common point.

*In a Hilbert plane, if line m is parallel to line l, then all the points on m lie on the same side of l.

*The notion of congruence of two triangles is undefined.

*An incidence geometry must have either the elliptic, or the Euclidean , or the hyperbolic parallel property.

Thank you!

Answer 1