Angle Measures

Honors Geometry
Do Now:
What is the distance between
a. R and Q?
b. S and R?
Do Now:
 The answers for the challenge problem packet is
posted to the right. Check them out and see which
ones you want me to go over
* Note: I refuse to do #7. That one was super challenge
and if you get it great, if not no worries :D if you want
to see how it’s done come by sometime and I’ll show
you :D
 Questions?
 Struggles?
 Ask Ask Ask!
 Ray: Part of a line, it has one endpoint and extends
indefinitely in the other direction.
 Notation: The name must begin with the endpoint.
 Ex:
 Opposite Rays: Rays at a 180 degree angle. Collinear.
 Ex:
Example One:
 Name three rays in the picture below
 Name two sets of opposite rays in the picture
 Angle: formed by two non-collinear rays that have a
common endpoint.
 Sides: The rays are the sides of the angle
 Vertex: The endpoint is called the vertex of the
 Notation: The middle letter must be the vertex of
the angle
 Ex:
Example Two:
Example Three:
Which angles
have R as a
What are the
sides of <1?
What is another
name for <SRP?
Example Four:
 1. Name the vertex of <4
 2. Name the sides of <BDC
 3. Write another name for <DBC
You Try!
 Determine the sides and vertex of each angle then
come up with THREE ways to write the angle.
 There are four types of angles
 Acute
 Obtuse
 Right
 Straight
Angles- Four Types
 Obtuse Angles: Angles between 90 < x < 180
 Ex:
Angles- Four Types
 Acute Angles: Angles with 0 < x < 90 degrees
 Ex:
Angles- Four Types
 Right Angles: 90 degree angles
 Denoted
 Ex:
by a little square.
Angles- Four Types
 Straight Angles: 180 degree angle
 i.e.
a straight line.
 EX:
Example Five:
 Classify each angle as right, obtuse, acute or straight.
 <MPR
You Try!
 Classify each angle as obtuse, right, straight or acute.
 <LMN
Example Six
Example Seven:
If m<ROT = 155 degrees, what are m<ROS and m<TOS?
You Try!
<DEF is a straight angle. What are m<DEC and m<CEF?
Practice Problems
 Try some on your own/in small groups
 As always if you are confused don’t hesitate to
ask me or your group members questions!
Exit Ticket