Warm Up
Over Lesson 1–4
Refer to the figure.
Name the vertex of 3.
What is another name
for ∠3?
Take Note
Adjacent Angles
Description: two angles that have the same vertex
and are next to each other.
Diagram:
Name: ∠1 𝑖𝑠 𝑎𝑑𝑗𝑎𝑐𝑒𝑛𝑡 𝑡𝑜 ∠2
Take Note
Linear Pair
Description: two adjacent angles that form a straight
line.
Diagram:
Name: ∠1 𝑎𝑛𝑑 ∠2 𝑓𝑜𝑟𝑚 𝑎 𝑙𝑖𝑛𝑒
All linear pairs add up to 180°
Take Note
Vertical Angles
Description: two angles across from each other that
are formed by intersecting lines.
Diagram:
Name: ∠1 𝑎𝑛𝑑 ∠3; ∠2 and ∠4
Vertical angles are congruent 
For Example
• Name a pair of vertical angles
For Example
• Name a linear pair
For Example
• Name a pair of adjacent angles
You Try
Name a pair of vertical angles, a linear pair,
and a pair of adjacent angles.
Take Note
Complementary Angles
Description: two angles that add to 90°
Diagrams:
Examples: ∠𝟏 𝒂𝒏𝒅 ∠𝟐; ∠𝑨 𝒂𝒏𝒅 ∠𝑩
Take Note
Supplementary Angles
Description: two angles that add to 180°
Diagrams:
Examples: ∠𝟑 𝒂𝒏𝒅 ∠𝟒; ∠𝑷 𝒂𝒏𝒅 ∠𝑸
For Example
• Find the value of x and y.
Homework
• HW 7: Pg.50 #’s 8-17, 19-21, 28- 30,49