Question 975283

find the center and radius of the circle

{{{x^2+y^2=16}}} 

{{{x^2+y^2=4^2}}} if you compare it to {{{(x-h)^2+(y-k)^2=r^2}}}, you see that {{{h=0}}} and {{{k=0}}} which means the center is at ({{{0}}},{{{0}}})

and {{{r=4}}}


{{{drawing( 600, 600, -10, 10, -10, 10,

circle(0,0,.14), locate(0.2,-0.3,C(0,0)),
 graph( 600, 600, -10, 10, -10, 10,-sqrt(-x^2+16), sqrt(-x^2+16))) }}}