of a circle is
I want to calculate
Area
Circumference
Radius
Diameter
All
  

Answer
Success!
C = 18π or 56.5487
d = 18
A = 81π or 254.469

↓Steps Explained:↓

A circle has radius = 9

Calculate Area, Circumference, Radius, Diameter

Calculate circumference (C):

C = 2πr

C = 2π * 9

C = 18π or 56.5487

Calculate diameter (d):

d = 2r

d = 2 * 9

d = 18

Calculate Area (A):

A = πr2

A = π * 92

A = 81π or 254.469

Final Answers

C = 18π or 56.5487
d = 18
A = 81π or 254.469

Take the Quiz


Related Calculators:  Unit Circle  |  Circle Equation  |  Annulus