Exam 1	Exam 2
axiomatic system	distance between points X and Y
consistent (axiomatic system)	angle between lines u and v
model (axiomatic system)	linear transformation
independent (axiomatic system)	affine transformation
complete (axiomatic system)	group of transformations
principle of duality (for an axiomatic system)	invariant of a transformation
isomorphic models	isometry
dual (of a statement)	direct isometry
polar	indirect isometry
pole	reflection
perspective from a point	rotation
perspective from a line	translation
Poincare' model	glide reflection
Klein model
sensed parallel
ultraparallel
asymptotic triangle
angle of parallelism
Saccheri quadrilateral
base
summit