###### Asked in Math and ArithmeticAlgebraGeometry

Math and Arithmetic

Algebra

Geometry

# What is the radius of a circle and its equation when its diameter touches the points of 2 -3 and 8 7 on the Cartesian plane showing key stages?

## Answer

###### Wiki User

###### May 13, 2012 12:34PM

Points: (2, -3) and (8, 7)

Centre: (8+2)/2 and (7-3)/2 = (5, 2)

Radius: (8-5)2+(7-2)2 = 34 and the square root of this is the radius

Equation: (x-5)2+(y-2)2 = 34

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