Giúp mik vsssssssssssss ạ.............

`(x-a)^2+(y-b)^2=R^2`

$\Leftrightarrow$ `x^2-2ax+a^2+y^2-2by+b^2-R^2=0`

$\Leftrightarrow$ `x^2+y^2-2ax-2by+c=0`

Với `c=a^2+b^2-R^2`