Geometry - Warm Up 8
Name_________________________
1. Find the coordinates of the midpoint of the segment with the given endpoints.
J(–7, –5) and K(–3, 7)
2. The endpoints of a segment are given. Find the coordinates of the midpoint. Then use the distance
formula to find the length of the segment.
E(1, 4) and F(5, 1)
3. The midpoint of BC is M(–2, 7). One endpoint is B(4, 3). Find the coordinates of endpoint C.
__________________________________________________________________________________
Today:
 You will learn how to classify angles
 You will learn how to identify and apply angle relationships
 At the end of class you will be able name and classify angles, add angles and solve for missing values
when given information about a pair of angles.
Geometry
Notes
Measuring and Classifying Angles & Angle Pair Relationships
Angle names –
C
Vertex –
A
B
Sides –
Example 1
Name the three different angles in the diagram.
H
G
I
J
Classification of Angles
Type
Measure
Sketch
Acute
Right
Obtuse
Straight
R
Angle Addition
S
P
T
Example 2
Given that m  CDE = 140°, find m  CDF and m  FDE.
F
C
(4x - 8)
(5x + 13)
D
E
An ______________________________________ is a ray that divides an angle into two congruent
angles.
Example 3
In the diagram, SP bisects  RST, and m  RSP = 19°. Find m  RST.
R
S
P
T
Two angles are _____________________________ if the sum of their measures is 90°.
Two angles are _____________________________ if the sum of their measures is 180°.
Two angles are _____________________________ if they share a common vertex and side, but have
no common interior point.
Example 4
a. Given that  1 is a complement of  2 and m  1 = 64°, find m  2.
b. Given that  3 is a supplement of  4 and m  4 = 28°, find m  3.
Example 5
Given that  ABC and  CBD are supplementary, find the value of x and the measures of each angle.
C
(4x + 8)
A
B
(x + 2)
D
Two adjacent angles are a ______________________________ if they form a 180° angle, in other
words, a straight line. The angles are also supplementary.
Two angles are ________________________ if their sides form two linear pairs. Vertical angles are
always congruent.
Example 6
Two angles form a linear pair. The measure of one angle is 4 times the measure of the other. Find
the measure of each angle.