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Equation of a circle

4 videos
3 skills
You know that a circle can be viewed as the set of all points that whose distance from the center is equal to the radius. In this tutorial, we use this information and the Pythagorean Theorem to derive the equation of a circle.

Equation of a circle in factored form

PRACTICE PROBLEMS
Find the center and radius of a circle given the equation in factored form.

Equation of a circle in non-factored form

PRACTICE PROBLEMS
Find the center and radius of a circle given the equation in unfactored form.