Question

whats an equation of a circle? :)

Answer 1

The equation of circle having the centre at Origin (0,0) and radius "r" is given by:

\[x ^{2} + y ^{2} = r ^{2}\]

Answer 2

The equation of circle having the centre at point (a,b) and radius "r" is given by:

\[(x-a)^{2} + (y-b)^{2} = r ^{2}\]