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Determine the radius and centre coordinates of a circle with equation expressed in expanded form.

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Write down the radius and the coordinates of the centre of the following circle

\n

$\\var{equation}$

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We need to begin by completing the square on the $x-$terms and on the $y-$ terms:

\n

$\\var{equation}$

\n

$\\var{completedsquares} = 0$

\n

$\\var{simplifiedequation}$

So the circle has radius = $\\var{radius}$ and centre $C = (\\var{centrex},\\var{centrey})$

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Centre = ( [[0]],[[1]] )

\n

Radius =  [[2]]

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