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ASAP What is the lateral area of this regular octagonal pyramid?? Explain your answer if you can plz thanks

ASAP What is the lateral area of this regular octagonal pyramid?? Explain your answer-example-1
User Paniq
by
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2 Answers

3 votes

Answer:

Hello! The correct answer is 298.7
cm^(2)

Explanation:

I am just confirming!

User Moniquea
by
6.6k points
6 votes
The lateral area would be 298.7 cm².

The lateral area is the area of all of the lateral faces of the pyramid. There are 8 triangles making up the lateral faces. Each has a base of 6.6. The formula for the area of a triangle is

A=1/2bh,

so we still need the height of the triangle.

The height of each lateral triangle is the slant height of the pyramid. The slant height of the pyramid forms a right triangle with the height of the pyramid and the "radius" as it were of the pyramid. Thus we use the Pythagorean theorem:

8²+8²=h²
64+64=h²
128=h²
√128=√(h²)
8√2 = h

Substituting this into our area formula we have:
A=1/2(6.6)(8√2)

We will go ahead and multiply this by 8, since there are 8 lateral faces:
LA=8(1/2)(6.6)(8√2)
LA = 298.7
User Paul Fisher
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