The base of a trapezoidal pyramid is square. Its base area is 100 square cm, and its lateral surface area is 260 square cm. What is the height of the pyramid?
Show answer & explanation
Correct answer: B
Explanation
Base area = 100 cm² ⇒ Side = 10 cm
Lateral surface area = 260 cm²
LSA = 2aℓ
ℓ² = h² + (a/2)²
2 × 10 × ℓ = 260
20ℓ = 260
ℓ = 13
13² = h² + 5²
169 = h² + 25
h² = 144
h = 12 cm