circle

Related Questions

• The circles ${{x}^{2}}+{{y}^{2}}=9$ and ${{x}^{2}}+{{y}^{2}}-12y+27=0$ touch each other. The equation of their common tangent is

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• If OA and OB be the tangents to the circle ${{x}^{2}}+{{y}^{2}}-6x-8y+21=0$ drawn from the origin O, then $AB =$

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