Transcript Pairs of Angles - Gateway School District

COURSE 3 LESSON 8-1
Pairs of Angles
If m
x° + m
DEF = 73º, find the measure of its supplement.
DEF = 180°
x° + 73° = 180°
x° + 73° – 73° = 180° – 73°
x° = 107°
The sum of the measures of
supplementary angles is 180º.
Substitute 73º for m
DEF.
Subtract 73º from each side.
Simplify.
The measure of the supplement of m
8-1
DEF is 107º.
COURSE 3 LESSON 8-1
Pairs of Angles
A right angle is divided into two angles. If the measure of
the larger angle is 67°, find the measure of its complement.
x° + 67° = 90°
x° + 67° – 67° = 90° – 67°
x° = 23°
The sum of the measures of complementary
angles is 90º.
Subtract 67º from each side.
Simplify.
The measure of the complement of 67º is 23º.
8-1
COURSE 3 LESSON 8-1
Pairs of Angles
of
m
In this figure, if m
GKJ and JKF.
DKE + 90° = 180°
m
DKE = 90°
DKH = 73°, find the measures
DKE and
FKE are supplementary.
Subtract 90º from each side.
8-1
COURSE 3 LESSON 8-1
Pairs of Angles
(continued)
m
KHE + 73° = 90°
KHE and
DKH are complementary.
m
KHE = 17°
Subtract 73º from each side.
m
GKJ = m
KHE = 17°
GKJ and
KHE are vertical angles.
m
JKF = m
DKH = 73°
JKF and
DKH are vertical angles.
8-1
COURSE 3 LESSON 8-1
Pairs of Angles
Use the diagram to answer Questions 1 and 2.
1. List all pairs of vertical angles.
AXD and BXC; AXB and
2. List any angles adjacent to
AXD and BXC
DXC
CXD.
3. If m AXB = 110°, find m DXC.
110°
4. An angle measures 57°. What is the measure of its supplement?
123°
5. An angle measures 24°. What is the measure of its complement?
66°
8-1