Circle Area and Circumference

Front

Definition of a circle

Back

round shape with all points equidistant from the center

Front

Formula for area of a circle

Back

latex="A = \pi r^2">

Front

Formula for circumference of a circle

Back

latex="C = 2\pi r">

Front

Back

latex="A = \pi (3)^2 = 9\pi">

Front

Back

latex="C = 2\pi (4) = 8\pi">

Front

Key term: Radius

Back

from center to any point on the circle

Front

Key term: Diameter

Back

Front

True/False: Diameter is twice the radius

Back

True

Front

True/False: Circumference is the area of a circle

Back

False

Front

Comparison: Radius vs Diameter

Back

is twice the radius