Circle Geometry Concepts

This video tutorial covers lessons 9.1 and 9.2, focusing on circle geometry, including definitions of radius, diameter, and chord. It explains how to calculate the circumference and area of circles using formulas. The video includes guided practice problems and advanced circle calculations. It concludes with homework instructions.

What is the term for a line segment with one endpoint at the center of a circle and the other on the circle itself?

• Tangent

• Radius

• Diameter

• Chord

Which of the following is the correct formula for the circumference of a circle?

• C = 2πr

• C = πr²

• C = 2πd

• C = πd

If the diameter of a circle is 10 units, what is its circumference using π ≈ 3.14?

• 31.4 units

• 15.7 units

• 62.8 units

• 20 units

What is the area of a circle with a radius of 7 units using π ≈ 3.14?

• 153.86 square units

• 38.5 square units

• 49 square units

• 21.98 square units

Which formula represents the area of a circle?

• A = πr²

• A = 2πd

• A = 2πr

• A = πd

If the circumference of a circle is 44 units, what is the diameter using π ≈ 3.14?

• 22 units

• 28 units

• 14 units

• 7 units

What is the relationship between the circumference and the area of a circle?

• C² = 4πA

• C = 4πA

• C = πA

• C² = πA

How do you find the radius if you know the diameter of a circle?

• Take the square root of the diameter

• Square the diameter

• Divide the diameter by 2

• Multiply the diameter by 2

What is the value of π to two decimal places?

• 3.16

• 3.13

• 3.14

• 3.15

If a circle has a circumference of 66 units, what is the approximate diameter using π ≈ 3.14?

• 21 units

• 22 units

• 23 units

• 20 units