Upload
augusta-osborne
View
223
Download
0
Tags:
Embed Size (px)
Citation preview
Lesson 9-3 Pages 447-451
Angles
Lesson Check 9-2
What you will learn!1. How to measure and draw angles.
2. How to classify angles as acute, right, obtuse, or straight.
PointPoint DegreeDegree
RayRay ProtractorProtractor
LineLine Acute angleAcute angle
AngleAngle Right angleRight angle
VertexVertex Obtuse angleObtuse angle
SideSide Straight angleStraight angle
What you really need to know!An angle is made up of two rays that have a common endpoint, called the vertex.
The most common unit of measure for angles is the degree. There are 360° in a circle.
Angles are measured using protractors.
S
R
W
Example 1:
Use a protractor to measure RSW.
42°
U M
Example 1B:
Find the measures of GUM, SUM, BUG.
G
S
B
U M
mGUM=120°; mSUM=32°; mBUG=60°;
G
S
B
Example 2:
Draw R having a measure of 145°.
145°R
Example 3:
Classify the angle as acute, obtuse, right, or straight.
Acute
Example 3:
Classify the angle as acute, obtuse, right, or straight.
Straight
Example 3:
Classify the angle as acute, obtuse, right, or straight.
Obtuse
Example 4:
The diagram shows the angle between the back of a chair and the seat of the chair. Classify this angle.
Obtuse
Page 449
Guided Practice
#’s 3-9
Pages 447-449 with someone at home and
study examples!
Read:
Homework: Pages 450-451
#’s 10-34 all
#’s 37-51
Practice Quiz 1 #’s 1-5Lesson Check 9-3
Page
745
Lesson 9-3
Lesson Check 9-3