GCSE Polygons website File
... Students should be able to: distinguish between acute, obtuse, reflex and right angles name angles use one lower-case letter or three upper-case letters to represent an angle, for example x or ABC understand and draw lines that are parallel understand that two lines that are perpendicular ...
... Students should be able to: distinguish between acute, obtuse, reflex and right angles name angles use one lower-case letter or three upper-case letters to represent an angle, for example x or ABC understand and draw lines that are parallel understand that two lines that are perpendicular ...
Coxeter notation
In geometry, Coxeter notation (also Coxeter symbol) is a system of classifying symmetry groups, describing the angles between with fundamental reflections of a Coxeter group in a bracketed notation, with modifiers to indicate certain subgroups. The notation is named after H. S. M. Coxeter, and has been more comprehensively defined by Norman Johnson.