Question

Mencari jari jari,garis pelukis,luas alas dan luas selimut pada kerucut dik= t=21cm v=792cm3,answer please

Answer 1

Volume kerucut = 1/3 x πr² x t
792 = 1/3 x 22/7 x r² x 21
2376 = 66  x r²
r² = 36
r = 6 cm

luas alas = πr²
= 3,14 x 6 x 6
= 113,04 cm²

garis pelukis (s)
s² = t² + r²
s² = 21² + 6²
s² = 441 + 36
s² = 477
s = 21,9 cm

luas selimut = πrs
= 3,14 x 6 x 21,9
= 412,596 cm²

Maaf kalau salah^^

Answer 2

792 = 1/3 × 22/7 × r^2 × 21
792 × 3 × 7/22 × 21 = r^2
r^2 = 36
r = 6 cm

s^2 = 6^2 + 21^2
s^2 = 36 + 441
s^2 = 477
s = 21,84 cm

Luas alas = 3,14 × 6 × 6
= 113,04 cm^2

Luas selimut = 3,14 × 6 × 21,84
= 18,84 × 21,84
= 411,4656 cm^2