Perbandingan jari-jari dan tinggi sebuah kerucut adalah 3:4 jika volume kerucut itu 96phi cm3 maka luas selimut kerucut itu adalah .. a. 60phi b. 30phi c. 24phi d. 20phi
Immanuelle
Kerucut r:t = 3:4 vkerucut = 1/3 pi r^2 t = 96pi pi habis r^2 t = 288 9x^2 4x = 288 36x^3 = 288 x^3 = 8 x = 2 r = 3.2 = 6 t = 4.2 = 8 s^2 = 8^2 + 6^2 s = 10 Ls = pi r s Ls = pi x 6 x 10 Ls = 60 pi
r:t = 3:4
vkerucut = 1/3 pi r^2 t = 96pi
pi habis
r^2 t = 288
9x^2 4x = 288
36x^3 = 288
x^3 = 8
x = 2
r = 3.2 = 6
t = 4.2 = 8
s^2 = 8^2 + 6^2
s = 10
Ls = pi r s
Ls = pi x 6 x 10
Ls = 60 pi