Untuk π=22/7 hitunglah panjang jari2 lingkaran yang luasnya A.440cm,B.154cm

phi = 22/7

a. L lingkaran = phi x r^2
440 = 22/7 x r^2
(440 x 7) / 22 = r^2
3080/22 = r^2
140 = r^2
r = akar 140
= 11,83 cm

b. L lingkaran = phi x r^2
154 = 22/7 x r^2
(154 x 7) / 22 = r^2
1078/22 = r^2
49 = r^2
r = akar 49
= 7 cm

semoga membantu:)