Question 100031
{{{SA=4(pi)r^2}}}
{{{86(pi)ft^2=4(pi)r^2}}}
divide each side by {{{(pi)}}}, then the {{{(pi)}}}cancels;
{{{86ft^2=4r^2}}}
divide each side by 4;
{{{86/4=r^2}}}
{{{21.5=r^2}}}
{{{sqrt(21.5)=sqrt(r^2)}}}
4.64=r
diameter = 2(4.64)=9.28
:)