Partner Vocabulary NotesPartner Vocabulary Notes
Share a copy of Buckle Down, Page 163-164
Complete foldable with vocabulary word, definition and picture.
10 minutes
““Parts of a Circle” OrganizerParts of a Circle” Organizer
Create a class poster with all parts of the circle labeled. (see next slides)
DIAMETERDIAMETER
DIAMETER is the distance through the CENTER of the circle.
It is twice as large as the radius.
d =diameterr= radius
Circumference Circumference
Circumference is the distance around the circle.
To find the circumference of a circle, you have to know the diameter or radius.
Diameter
radi
usThe circumference of a circle is the distance around the outside
The area of a circle is the space inside it
The circumference is found using the formula:
C=πd or C= 2rπ
(since d=2r)
The area is found using the formula
A= π r2
BEFORE WE BEGIN FINDING CIRCUMFERENCE AND AREA, YOU MUST REMEMBER THIS…
For every problem, you must show:
The Formula
The Substitutions
Final Answer
Labeling
A pizza place has an 8” diameter, 12” diameter, and a 16” diameter pizza. What is the area and circumference of those pizzas?
AND THE ANSWERS ARE (approximately)AND THE ANSWERS ARE (approximately)…..…..
8” Pizza:circumference: 25.12” area: 50.24 in2
12” Pizza:circumference: 37.68”area: 113.04 in2
16” Pizza:circumference: 50.24”area: 200.96 in2
Independent PracticeIndependent Practice
Buckle Down
Page 165-166
All problems
Homework if not complete
Using Circumference Formula and Using Circumference Formula and Area of a Parallelogram for Area of Area of a Parallelogram for Area of a Circlea Circle
Buckle Down
Page 164
Use Paper Plates or segmented circle to demonstrate