Download Angle Relationships

Angle Relationships
Angle Symbology
Symbol
A
mX
Meaning
Angle “A”
The measure of angle “X”
A  B
ABC
Angle “A” is congruent to angle “B”
AB  CD
Line segment AB is perpendicular to segment
CD
a b
Angle ABC where point B is the vertex
Line “a” is parallel to line “b”
Adjacent Angles
Have a common vertex
and a common side, but
no common interior
points.
Common
Side
1
2
1 and 2 are
Vertical Angles
Are formed by 2 intersecting
lines and are opposite each
other. Vertical angles are
congruent. They have the
same measure
5 and 3 are
4 and 6 are
6
5
4
3
Supplementary Angles
W
Two angles are supplementary
if the sum of the measures of
the two angles is 180⁰
X
Y
WYX and WYZ are
Angles
Two adjacent angles that for a straight line are supplementary to each other
Z
Complementary Angles
R
Two angles are Complementary if
the sum of the measures of the
two angles is 90⁰
V
S
VSR and VST are
Angles
T
Perpendicular Lines (  )
R
Perpendicular lines are two
lines that intersect to form a
right angle
A
S
B
T
E
D
C
G
F
Name a pair of adjacent angles and a
pair of vertical angles in the figure at
the right
H
K
G
145⁰
J
I
The adjacent angles are HGK and KGJ; KGJ and
; JGI and
The vertical angles are JGI and
; IGH and
; HGI and
Since vertical angles are congruent, mHGK  mJGI 
Are 3 and 4 adjacent angles? Explain
1.
2.
3
4
3
4
3. Does every angle have a
complement? Explain
3.
4
3