Unit 7: Geometry with Circles Day 1

Unit 7: Geometry with Circles Day 1

Parts of a Circle

• Center: The center post point of a circle that is equidistant from any point on the edge.

• Radius: A line that goes from the center of the circle to the edge of the circle

• Diameter: A line that goes through the center from one edge of the circle to another edge.

Parts of a Circle

• Circumference: The perimeter around the circle

Multiple Choice

Determine which part of the circle the image is depicting.

• Radius

• Diameter

• Circumference

• Center

Multiple Choice

Determine which part of the circle the image is depicting.

• Radius

• Diameter

• Circumference

• Center

Multiple Choice

Determine which part of the circle the image is depicting.

• Radius

• Diameter

• Circumference

• Center

Multiple Choice

Determine which part of the circle the image is depicting.

• Radius

• Diameter

• Circumference

• Center

Relationship between Radius and Diameter

• The radius is from the center to the edge of a circle.

• The diameter is from one end of the circle to the other, passing through the radius.

• Radius is 1/2 the size of diameter

• Diameter is 2 times the size of the radius

Multiple Choice

The diameter is shown. Determine the radius.

• Diameter = 11 mm

  Radius = 5 mm

• Diameter = 11 mm

  Radius = 5.5 mm

• Diameter = 11 mm

  Radius = 22 mm

Multiple Choice

Determine the Radius and Diameter.

• Radius = 7 cm

  Diameter = 14 cm

• Radius = 7 cm

  Diameter = 3.5 cm

• Radius = 3.5 cm

  Diameter = 14 cm

• Radius = 3.5 cm

  Diameter = 7 cm

Multiple Choice

What is the relationship between diameter and radius?

• The radius is always 2 times the diameter.

• The radius is always 1/2 the diameter.

• The diameter is always 1/2 the radius.

• There is no relationship between the two.

Multiple Choice

Determine Radius.

• Radius = 63 ft

• Radius = 126 ft

• Radius = 31.5 ft

• Radius = 21 ft

Poll

How do you feel about the lesson?

• 1. I don't understand it.

• 2. I understand a little, but I need more help.

• 3. I understand it.

• 4. I understand it and I can teach it to someone else!