Question 969385
{{{A=2pi*r*h}}} h for height or distance between the circular ends.  A for area of surface.




If {{{k=r=h}}}, then {{{A=2pi*k^2}}}


{{{k^2=A/(2*pi)}}}


{{{k=sqrt(A/(2pi))}}}


{{{k=sqrt(A)sqrt(2pi)/(2pi)}}}


{{{highlight_green(k=sqrt(A*2pi)/(2pi))}}}------This is also the radius.


The diameter is two times k=r;
diameter is {{{highlight(sqrt(A*2pi)/pi)}}}.