Day 1 CW Intro to circles Answers.notebook
November 13, 2013
Complete the table:
Radius
Diameter
Circumference
Area
6
16
25π
14π
Introduction to Circles
Objective: Students will learn vocabulary words for circles. Students will apply their knowledge of area and circumference given a diagram.
Day 1 CW Intro to circles Answers.notebook
Diameter: Is a chord that has the center of the circle as one of its points
Chord: A line segment whose endpoints are points on the circle
Intro to Circles
Radius: Is a line segment from the center of the circle to any point on the circle.
All radii (plural)of the same circle are congruent.
November 13, 2013
Types of Arcs
Arc­ any part of the circle.
Minor arc­ arc with measure less than 1800.
Use 2 letters to label
Major arc­ arc with measure greater than 1800.
Named with three points. Use 3 letters to label
Semicircle­ arc equaling 1800.
Intercepted arc­ arc intercepted by an angle.
Day 1 CW Intro to circles Answers.notebook
November 13, 2013
Name the following:
4 radii:
E
2 diameters:
F
H
O
G
4 chords:
4 minor arcs:
2 major arcs:
2 semicircles:
Types of angles
Central Angle: An angle whose vertex is the center of the circle
The measure of the central angle is = to its intercepted arc.
Inscribed Angle: An angle whose vertex lies on the circle and whose sides contain chords of the circle
The measure of the inscribed angle is = to 1/2 its intercepted arc.
Day 1 CW Intro to circles Answers.notebook
November 13, 2013
Practice
Find: (
(
m AC
B
m ACB
m < COB
m ADB
m ABC
(
60
A
m CB
( ( (
C
m CAB
O
D
<1's intercepted arc:
<2's intercepted arc:
<3's intercepted arc:
<4's intercepted arc:
Find the value of x.
1.
2700
2.
x
o
o
x
450
Homework page 440­441 #4, 5, and 8
Day 1 CW Intro to circles Answers.notebook
3.
November 13, 2013
4.
500
x
x
700
5.
x
6.
y
o y
o
x
z
2200
Find:
x
<y
<z
2600
Day 1 CW Intro to circles Answers.notebook
Homework: Worksheet
November 13, 2013