Classifying Angles
Angles can be classified into 4 different groups. Think of the groups as
different classes that they could be sorted into…
Acute
less than 90°
Right
equal to 90°
Obtuse
greater than 90°,
but less than
180°
Straight
equal to 180°
The square notation indicates
that the angle is a right angle.
NAMING Angles
Just like you spell your name with letters, angles spell their name with
letters. Below are examples how angles can be named 3 different ways.
Note that when using three letters, the vertex is ALWAYS in the middle.
Angle H
Angle CHA
Angle AHC
H
Angle F
Angle XFT
Angle TFX
C
X
T
A
F