Coordinate Geometry - Equation of a Circle (GRE)


These lessons are part of a series of lessons for the quantitative reasoning section of the GRE revised General Test. In these lessons, we will learn how to graph and write the equations of circle.




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Equation Of Circle Tutorial

Equation of a Circle

The graph of an equation of the form (xa)2 + (yb)2 = r2 is a circle with its center at the point (a, b) and with radius r.

This video looks at using equations of circles to find the center and the radius of a circle to graph it, as well as, writing an equation for a circle, given the center and radius, or a point on the circle. It includes four examples.

This video shows how to graph and write equations of circles.




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