Question

A circle of radius 2units and it's centre at(3,1). Find the equation of the circle in expended form

Answer 1

`\textit{equation of a circle}\\\\ (x- h)^2+(y- k)^2= r^2 \hspace{5em}\stackrel{center}{(\underset{h}{3}~~,~~\underset{k}{1})} \qquad \stackrel{radius}{\underset{r}{2}} \\\\[-0.35em] ~\dotfill\\\\( ~~ x - 3 ~~ )^2 ~~ + ~~ ( ~~ y-1 ~~ )^2~~ = ~~2^2\implies (x -3)^2 + (y -1)^2 = 4 \\\\\\ (x^2-6x+9)+(y^2-2y+1)=4\implies x^2-6x+y^2-2y+10=4 \\\\\\ ~\hfill~ {\Large \begin{array}{llll} x^2-6x+y^2-2y+6=0 \end{array}} ~\hfill~`