Circumference and Parts of a Circle

Area and Circumference of a Circle

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Parts of a Circle

• Radius: line segment that goes from the center to the edge of the circle (HALF the DIAMETER)

• Diameter: line segment that goes from edge to edge on a circle (TWICE the RADIUS)

• Circumference: the distance around the outside of a circle (AKA perimeter)

Area of a Circle

Area is the space inside of the circle.

Circumference

Unlike area, there are two formulas that can be used to find the circumference of a circle:

One when given the diameter

and

One when given the radius.

Delta Math

Area of a Circle (rounded)

Circumference (rounding)