A right circular cone has base radius 5 and height 12. First find the slant height using the Pythagorean theorem, then find the cone's TOTAL surface area (lateral + base).
ASlant height = 12; total surface area = 267.04 sq. units
BSlant height = 13.0; total surface area = 282.74 sq. units
CSlant height = 13.0; total surface area = 267.04 sq. units
DSlant height = 13.0; total surface area (lateral only) = 204.2 sq. units
Explanation
Slant height = √(r²+h²) = √(5²+12²) = √169 = 13.0. Lateral surface area = πr×(slant) = π(5)(13.0) ≈ 204.2. Base area = πr² = π(5)² ≈ 78.54. Total = 204.2 + 78.54 ≈ 282.74 sq. units.
¿Listo para empezar a practicar?
Free sample questions available. No credit card required.