A necessary and sufficient condition for the curve of equation (x-a) ^ + (y-b) ^ = R ^ to pass through the origin

If and only if y = 0, a point at the intersection of x-axis passes through the origin
(x-a)^+(y-b)^=r^
x=a±√(r^2-b^2)=0
The necessary and sufficient conditions for a curve to pass through the origin are as follows:
r>=b,a=±√(r^2-b^2)

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