# Equation of a Circle

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More Lessons for Grade 9

Math Worksheets

Videos, worksheets, games and activities to help Geometry students learn how to find the equation of a circle given information the radius, center, or a point the circle goes through and the center and how to sketch a circle given its equation.

What is the equation of a circle in standard form?
The equation of a circle is (x - h)2 + (y - k)2 = r2, where (h,k) is the center of the circle and r is the radius.

Covers writing equations of circles given information like the radius, center, or a point the circle goes through and the center.
Graphing a circle given its equation in standard form
Plotting center and radius of a circle; sketch.

Writing the Equation of a Circle in Standard Form
This video shows a specific example of how to find the center and radius when given the equation of a circle.

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