Question 1126197
the standard form and the general form of the equation of each circle with radius {{{r }}} and center ({{{h}}},{{{k}}}) is:

{{{(x-h)^2+(y-k)^2=r^2}}}



1. if  {{{r=2/3}}};  ({{{h}}},{{{k}}})= ({{{0}}},{{{0}}}), we have

{{{(x-0)^2+(y-0)^2=(2/3)^2}}}

{{{x^2+y^2=4/9}}}


{{{drawing( 600, 600, -3, 3, -3, 3,
circle(0,0,.05),locate(0.1,0.1,C(0,0)),
 graph( 600, 600, -3, 3, -3, 3,-sqrt(4/9-x^2) ,sqrt(4/9-x^2))) }}}