Question

Find the equation in general form of the circle with center at the origin and radius equal 6.

Answer 1

$\bf \textit{equation of a circle}\\\\ (x-{{ h}})^2+(y-{{ k}})^2={{ r}}^2 \qquad \begin{array}{lllll} center\ (&{{ h}},&{{ k}})\qquad radius=&{{ r}}\\ &0&0&6 \end{array}\\\\ -------------------------------\\\\ (x-0)^2+(y-0)^2=6^2\implies x^2+y^2=36$