Which do you think is easier and why: Writing the equation of a circle, given the center and the radius; or writing the equation, given the center and a point on the circle? Give examples to support your point of view. How can you tell from the equation of a circle whether or not a given point lies in the interior of the circle?

Question

anonymous · Answer

first one,because you dont have to find the lenght of the radius

anonymous · Answer

if center is A$$r<AB$$,then point B is outside
$$r>AB$$,then point inside
$$r=AB $$ on the circle