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A pyramid composed of four equilateral triangles, called a tetrahedron, has a one-side length of 5 meters. What is its surface area? Round the answer to the nearest tenth.

User ZorbaTHut
by
7.9k points

2 Answers

3 votes

Answer:

43.3

Explanation:

User Denis Stafichuk
by
8.2k points
3 votes
The area of an equilateral triangle is (1/2)bh. The base is 5, so using the Pythagorean theorem we get h by:
5² = (5/2)² +h²
h = √18.75
h = 4.33
So the area of one face is (1/2)(5)(4.33) = 10.825m²
The total area is 4(10.825m²) = 43.3m²
User Nelle
by
8.5k points
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