Circle Basics

Front

What is the radius of a circle whose diameter is 40 ft?

Back

20 ft

Front

The _____ is the distance from the center to any point on the circle.

Back

radius

Front

Every circle can be divided into _______ units called degrees.

Back

360

Front

Point C is...

Back

On the circle

Front

What is the diameter of this circle if the radius is 3.5 ft?

Back

7 ft

Front

What is the formula for the circumference of a circle?

Back

C = 2πr

Front

What is the area of a circle with a radius of 5 ft?

Back

78.54 ft² (Area = πr²)

Front

What do you call a line segment that passes through the center of the circle and has endpoints on the circle?

Back

Diameter

Front

If the radius of a circle is doubled, what happens to the area?

Back

The area increases by a factor of four.

Front

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

Back

Diameter = 2 × Radius