Radius of Circle Equation

Equation of circle on the cartesian plane with centre (h, k) is given as,

(x − h)2 + (y − k)2 = r2

Where (x, y) is the locus of any point on the circumference of the circle and ‘r’ is the radius of the circle.

If the origin (0,0) becomes the centre of the circle then its equation is given as x2 + y2 = r2, then Radius of Circle Formula is given by :

(Radius) r = √( x2 + y2 )

Radius of Circle

Radius of Circle: The radius of a circle is the distance from the circle’s center to any point on its circumference. It is commonly represented by ‘R’ or ‘r’. The radius is crucial in nearly all circle-related formulas, as the area and circumference of a circle are also calculated using the radius.

In this article, we are going to learn about the Radius of the Circle in detail, including its Formula, Equation, and How to Find it with the help of Examples.

Table of Content

  • What is the Radius of Circle?
    • Radius of a Circle Definition
  • Diameter of Circle
  • Radius, Diameter and Chord
    • Secant to Circle
    • Tangent to Circle
    • Non-Intersecting Lines
  • Radius Formula 
  • How to Find Radius of Circle?
  • Radius of Sphere
  • Radius of Circle Equation
  • Chord of Circle Theorems
  • Radius of Circle Examples
  • Practice Questions on Radius of Circle

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