Area of Circle
A = pi*r*r
Definition
Area enclosed by a circle equals pi times the square of its radius.
Variables
| Symbol | Meaning |
|---|---|
A |
Area |
r |
Radius |
Calculator
Area
—
cm²
Worked Example
r = 7 cm A = π × 7² = 153.94 cm²
Related Formulas
Volume of Cube
volume cube a cubed
Tangent Perpendicular to Radius
tangent perpendicular radius at point of contact
Area of Trapezium
area trapezium
Study Tools
Question
Area of Circle
Tap to reveal formula
Answer
A = pi*r*r
Area enclosed by a circle equals pi times the square of its radius.
Quick Quiz
In Area of Circle, what does r represent?
Used In
- Circles
- Mensuration
Frequently Viewed Together
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c*c = a*a + b*b
Expansion of 2×2 Determinant
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