butuh jawaban cepat

L = πr (r + s)
L = π . 9 (9 + √12²+9²)
L = π . 9 (9 + √144+81)
L = π . 9 (9 + √225)
L = π . 9 (9 + 15)
L = π . 9 . 24
L = π . 216 cm²

jawaban : D . 216 π cm²

sisi miring kerucut = √r²+t²
= √9²+12²
= √81+144 = √225
= 15 cm
Lp kerucut = πr² + πrs
= π.9² + π.9.15
= 81 π + 135 π
= 216π cm² (D)