# Area of a Circle

What is the formula for the area of a circle? What does it relate to that you already know?

Straighten the circumference of the circle using the slider.
Click the dissect checkbox to dissect the circle.
Rearrange the dissected parts using the green slider.
What shape does the figure look like when you rearrange it?
You can increase number of parts using the red slider.
As you increase the number of parts, what does the figure begin to look like?
What are the dimensions of that shape?
What is the formula for the area of that shape?
What do you think the formula for the area of a circle is?
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