NC Math 3 Review: Circles

Front

What does 'circumference' mean?

Back

Distance around a circle.

Front

Write the equation of a circle with center (7, 0) with radius 3.

Back

(x - 7)² + y² = 9.

Front

Find the center if the endpoints of the diameter are at (-12, -7) and (3, 5).

Back

(-4.5, -1).

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where r is the radius.

Front

What is the formula for the area of a circle?

Back

A = πr², where r is the radius.

Front

If a circle has a radius of 5, what is its circumference?

Back

C = 2π(5) = 31.4.

Front

If a circle has a radius of 4, what is its area?

Back

A = π(4)² = 50.24.

Front

What is the relationship between the diameter and radius of a circle?

Back

Diameter = 2 × Radius.

Front

How do you find the radius if you know the circumference?

Back

Radius = Circumference / (2π).

Front

What is the diameter of a circle with a radius of 6?

Back

Diameter = 2 × 6 = 12.