## Reflection: Adjustments to Practice Circumference from Area / Area from Circumference - Section 1: Teacher Model

In the reflection from the previous lesson I suggested setting up the lesson so that students discover how to find the radius and diameter when given the circumference or area of a circle.  Using that approach allowed me to skip most of that lesson and combine it with this lesson.  This saved me a day in my unit which I could use later for re-teaching or extending a concept!

I started this warmup with a short refresh on finding the radius and diameter.  I then allowed students to try the examples on their own.  I only had to help a few students find the radius and diameter.  Most then saw that once they find the radius from a given circumference they can then use that radius to find the area.

Suggested Changes

# Circumference from Area / Area from Circumference

Unit 6: Geometry
Lesson 11 of 37

## Big Idea: This is a simple lesson that eradicates simple mistakes when finding the circumference from area or vice versa.

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45 minutes

### Grant Harris

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