Question 636105
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The distance from the center of a circle to a point on the circle is the radius.  So use the distance formula


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ r\ =\ d\ =\ sqrt{(x_1\ -\ x_2)^2\ +\ (y_1\ -\ y_2)^2}]


where *[tex \Large \left(x_1,y_1\right)] and *[tex \Large \left(x_2,y_2\right)] are the coordinates of the given points to determine the radius, then use the standard form of an equation of a circle centered at *[tex \LARGE \left(h,\,k\right)] with radius *[tex \LARGE r] to write your desired equation:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \left(x\ -\ h\right)^2\ +\ \left(y\ -\ k\right)^2\ =\ r^2]


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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