Answer
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C = 18π or 56.5487
d = 18
A = 81π or 254.469
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 56.5487d = 18
A = 81π or 254.469
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Related Calculators: Unit Circle | Circle Equation | Annulus