tolong master gmn maksudnya

r = 1/2 d = 3 m

s^2 = t^2 + r^2
s^2 = 4^2 + 3 ^2
s^2 = 16 + 9
s^2 = 25
s = 5 m

L. bahan
= phi. r ( r + s )
= 3,14 . 3 ( 3+5 )
= 9,42 (8)
= 75,36 cm kuadrat

maap kalo salah :)