1. 02.13.2018 Ticket in the Door (Rituals and Routines)
Where should you place your book bag in Mrs. Janice Class?
Have you placed your book bags where they should go? If not do so now!
What is the call and response for Mrs. Janice’s Class?
Is it appropriate to talk during instruction time in Mrs. Janice’s Class?
Is it ok to talk while my peers have the floor to talk?
Can I eat sun flower seeds and chips in Mrs. Janice’s Class?
Should I be at or behind Mrs. Janice’s desk?
Respect, Respect, Respect your teacher and your peers)!!!!!!
Format your papers for Cornell notes. Topic: Area of a Circle E.Q. How can I calculate the area of a circle?
Agenda
Ticket in the Door (Rituals and Routines)
Cornell Notes (Area of a Circle)
Wrap-Up

2. What is the formula relating the circumference to the diameter?
center
Diameter
Radius

3. What is the formula relating the circumference to the Radius?
center
Diameter
Radius

4. Today we are going to find the area of circles

5. The area around the outside is the circumference
What you need to know
DIAMETER
RADIUS
The area around the outside is the circumference

6. You can use the π button on your calculatorPi
People noticed that if you divide the circumference of a circle by the diameter you ALWAYS get the same answer
They called the answer Pi (π) , which is:
You can use the π button on your calculator

7. You can find the area of a circle by using the formula-
Area= π x Radius2

8. Example 1 Area= π x Radius2 Area= π x 72 = π x 49 = 153.93804
= 153.9cm2 (to 1dp)
7cm

9. Example 2
Area= π x Radius2
Area= π x 52
= π x 25
= 78.5
5cm

10. Example 1 Area= π x Radius2 Radius= 18cm ÷ 2 = 9cm Area= π x 92=
=254.3
18cm

11. Reference