Circles Circles Circles

Front

What is a radius of a circle?

Back

A radius is a line segment from the center of the circle to any point on its circumference.

Front

What is a diameter of a circle?

Back

A diameter is a line segment that passes through the center of the circle and has its endpoints on the circumference. It is twice the length of the radius.

Tags

CCSS.HSG.C.A.2

Front

How do you calculate the radius from the diameter?

Back

Divide the diameter by 2.

Tags

CCSS.7.G.B.4

Front

What is the formula for the area of a circle?

Back

A = π·r², where A is the area and r is the radius.

Tags

CCSS.7.G.B.4

Front

What is the formula for the circumference of a circle?

Back

C = 2·π·r or C = π·d, where C is the circumference, r is the radius, and d is the diameter.

Tags

CCSS.7.G.B.4

Front

What does the term 'circumference' refer to?

Back

Circumference is the distance around the circle.

Front

What is the area of a circle with a radius of 3 meters?

Back

A = π·(3)² = 28.27 square meters (approximately).

Tags

CCSS.7.G.B.4

Front

If a circle has a diameter of 10 meters, what is its radius?

Back

The radius is 5 meters.

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the length of the radius.

Tags

CCSS.7.G.B.4

Front

What is the area of a circle with a diameter of 8 meters?

Back

A = π·(4)² = 50.27 square meters (approximately).

Tags

CCSS.7.G.B.4