Question 1065332
{{{ A = (pi)r^2 }}}

{{{ A = 100 = (pi)r^2 }}}
    {{{  100/(pi) = r^2 }}}
    {{{ sqrt(100/(pi)) = r }}}
Re-writing:
    {{{ r = sqrt(100/(pi)) = highlight( 10 / sqrt(pi) )}}} inches

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