ACUTE ANGLE
RIGHT ANGLE
OBTUSE ANGLE
STRAIGHT ANGLE
REFLEX ANGLE
FULL ANGLE
An angle measuring greater than 0 degrees, but less than 90 degrees
An angle whose legs are perpendicular to one another
An angle measuring greater than 90 degrees, but less than 180 degrees
An angle measuring 180 degrees; a line
An angle measuring greater than 180 degrees, but less than 360 degrees
An angle measuring 360 degrees
j
m∠ s
90°
s
u
b
w
r
180°
m∠ w
m∠ b = 90°
m∠ u = 180°
Angle j is an acute angle because it is less than 90, but greater than 0.
180°
360°
m∠ r = 360°
Lesson Plans by Anna Warfield
Visual Aids for the Modern Classroom