227k views
5 votes
(Hurry) guys pls help me, i don’t understand what my teacher taught me

(Hurry) guys pls help me, i don’t understand what my teacher taught me-example-1
User ShaneKm
by
8.2k points

2 Answers

4 votes

Answer:

Explanation:

me too i dont know

User Antitoxic
by
7.7k points
3 votes

Answer:

  • 8 cm
  • ≈ 117.6 cm³

Explanation:

Total surface area:

  • A = 4(1/2*7*l) + 7² = 14l + 49, where l is a slant height

We are given:

  • A = 161 cm²

Find the value of l:

  • 14l + 49 = 161
  • 14l = 112
  • l = 112/14
  • l = 8 cm

Use Pythagorean to find the height h of the pyramid:

  • l² = h² + (7/2)²
  • 8² = h² + 3.5²
  • h² = 8² - 3.5²
  • h² = 51.75
  • h = √51.75
  • h ≈ 7.2 cm

Find the volume:

  • V = 1/3Bh
  • V = 1/3*7²*7.2
  • V = 117.6 cm³
User BalusC
by
7.8k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories