Step-by-step explanation:
the area of a circle is
A = pi × r²
the circumference of a circle is
C = 2 × pi × r
so,
A = pi × r² = 64 in²
r² = 64 / pi
r = sqrt(64 / pi) = 8×sqrt(1/pi) in
the circumference is then
C = 2 × pi × r = 2 × pi × 8×sqrt(1/pi) = 16×pi×sqrt(1/pi) =
= 28.35926161... in
