Key Topic
The FRAME Routine
Exploring Area of Circles
is about…
Using what we know about circles and π to help find the formula of a circle and using it to solve for its area.
Main idea
Area of Circles
Essential details
Fun Fact: Exploration of the
“Discovery of the Area Formula of a Circle”
Example: Area using radius, diameter, or Circumference.
#1. r = 12 mm
Looks like a Parallelogram.
Area = base*height
Base = half the circumference
Height = radius =
𝐶
=2=
2π𝑟
2
Area = 452.16 mm2
#2. d = 14 m
= πr
Area = 153.86 m2
r
Area = πr*r = πr2
#3. C = 4π ft
Area = 12.56 ft2
So What? (What’s important to understand about this?)
The area of a circle is equal to π times the radius squared.