Geometry

Equation of a Circle Calculator

Radius and expanded equation from center (h, k) and a point (x, y) on the circle.

Radius r

Equation

This free Equation of a Circle Calculator covers Radius and expanded equation from center (h, k) and a point (x, y) on the circle.

r² = (x−h)² + (y−k)². Other geometry tools are linked below.

Equation of a Circle Calculator — how it works

Radius and expanded equation from center (h, k) and a point (x, y) on the circle. Typical inputs are Center h, Center k, Point x and Point y. How it works beside the form states the identity the Equation of a Circle Calculator applies.

FAQ

How do I use the Equation of a Circle Calculator?

Open the Equation of a Circle Calculator, fill Center h, Center k, Point x and Point y, and read the result. r² = (x−h)² + (y−k)².

What formula does the Equation of a Circle Calculator use?

The Equation of a Circle Calculator uses the identity in How it works. In words: r² = (x−h)² + (y−k)².

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