Question

Assalamualaikum Ka Tolong Kerjakan Sama Pakai caranya​

Answer 1

Ingat ( Keliling = jumlah rusuk yang mengelilingi bangun)

Gambar 1
r = 10 cm
K = 2. (30-10) + πd
= 40 cm+ 3,14 . 20cm
= 40 cm + 62,8 cm
= 102,8 cm

Gambar 2
d = 21 cm
K = 28 cm + (28-21cm) +21cm + πd
= 28 cm + 7 cm + 21 cm + 22/7. 21cm
= 122cm

Gambar 3
d= 21 cm
K = 2 . 24 cm + πd
= 48 cm + 22/7 21cm
= 48 cm + 66cm
= 114 cm

Gambar 4
d= 14 cm
K = 2. 35 cm + 14 cm + ½ π d
= 70 cm + 14 cm + ½ 22/7. 14 cm
= 84 cm + 22cm
= 106 cm

Jadi keliling minimum adalah
Gambar 1 (A)