diketahui diameter lingkaran 70 cm berapa cm2 luasnya JAWAB : ...

phi . r^2
jari-jari = 1/2 diameter = 35 cm
22/7 × 35 × 35
= 22 × 5 × 35
= 3850 cm^2

r = 70/2 = 35
L = π.r2
= 22/7. 35.35
= 3850