Calculating Area and Circumference of Circles
Grade 9th Grade · Math · 45 min
What's Included
Learning Objective
I can calculate the area and circumference of circles given the radius or diameter.
Warm-Up Video
Miacademy & MiaPrep Learning Channel · 8:50
How to Calculate the Circumference and Area of Circles
Guided Notes
3 key concepts
- 1
The diameter is the distance across the center of the circle, while the radius is the distance from the center to the outer edge; the radius is half the diameter.
- 2
The circumference of a circle is the distance around the circle, and can be calculated using the formula C = πd or C = 2πr, where π is approximately 3.14.
- 3
The area of a circle is calculated using the formula A = πr², where r is the radius and π is approximately 3.14.
Practice Questions
8 questions · Multiple choice & Short answer
Exit Ticket
Quick comprehension check
“A circle has a diameter of 14 cm. What is its area? Show your work, using 3.14 as the approximation for π.”
Complete Lesson Package
Get all 3 ready-to-use resources:
