Tolong bantu jawab no 8 yaa..

L = 64π
π.r^2 = 64π
r^2 = 64π/π
r = √64
r = 8 cm

L = 64π cm²
Maka
L = 64π
⇒ πr² = 64π
⇒ r² = 64
⇒ r² = 8² 
⇒ r = 8 cm

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