[tex](x-x_0)^2+(y-y_0)^=r^2
(x-2)^2+(y-2)^=2[/tex]Firstly, we need to find out the radius of the circle
and this is accomplished by the distance formula[tex] r=\sqrt{(y_2-y_1)^2+(x_2-x_1)^2} \\
r=\sqrt{(2-1)^2+(2-1)^2} \\
r=\sqrt{1+1} \\
r=\sqrt{2}
hence:\\
\\
r^2=2[/tex]
then the equation of the circle is:
[tex](x-x_0)^2+(y-y_0)^2=r^2\\
\\(x-2)^2+(y-2)^2=2[/tex]
