jari jari dari 18 diameter 24

luas lingkaran
= π r kuadrat
= 3,14 × 18 × 18
= 3,14 × 324
= 1.017,36 cm2

d = 24 cm
r = 24 ÷ 2 = 12 cm
luas = π r kuadrat
= 3,14 × 12 × 12
= 3,14 × 144
= 452,16 cm2

semoga terbantu ^_^