no 12-17 jawab plisss

#12
Lp = 2 x (pl + pt + lt)
= 2 x (15 x 12 + 15 x 8 + 12 x 8)
= 2 x (180 + 120 + 96)
= 792 cm²

#13
Panjang rusuk kubus = 52 ÷ 4 = 13
Lp = r² x 6
= 13² x 6
= 169 x 6
= 1014 cm²

#14
Lp = r² x 6
864 = r² x 6
√(864 ÷ 6) = r
√144 = r
12 = r

#15
Lp kubus tanpa tutup = r² x 5
= 9² x 5
= 81 x 5
= 405 dm²

#16
L sisi = r²
2,25 = r²
r = √2,25
r = 1,5 dm

V = r³
V = 1,5³
V = 3,375 dm³

#17
Lp = 2 x (pl + pt + lt)
392 = 2 x (12 x l + 12 x 5 + l x 5)
392 = 24 x l + 120 + l x 10
392 - 120 = 24 x l + 10 x l
272 = l x (24 + 10)
272 = l x 34
l = 272 ÷ 34
l = 8 cm

Maaf kalau ada yang salah
Jadikan terbaik ya, thanks