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Does anybody know this? I got told it was 828.8 by someone and it was wrong.Find the surface area of the square pyranid

Does anybody know this? I got told it was 828.8 by someone and it was wrong.Find the-example-1
User Linto
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1 Answer

4 votes

Answer:

800 ft²

Explanation:

The total surface area of a square-base pyramid is given by the formula ...

A = s(s +2h) . . . . . . where s is the side length, h is the face slant height

In this problem, we need to find the slant height of a face in order to use this formula.

__

slant height

The distance from the middle of one edge of the base to the peak of the pyramid is the slant height of a face of the pyramid. It is the hypotenuse of a right triangle whose legs are the pyramid height, and half the width of the base. For this pyramid, that is a right triangle with legs 15 and 8.

The Pythagorean theorem is used to find the hypotenuse of that triangle:

c² = a² +b² . . . . square of hypotenuse = sum of squares of legs

c² = 15² +8² = 225 +64 = 289

c = √289 = 17

The slant height of a face of the pyramid is 17 ft.

total area

The area formula tells us the total surface area is ...

A = s(s +2h)

A = (16 ft)(16 ft + 2×17 ft) = (16 ft)(50 ft)

A = 800 ft²

The total surface area is 800 square feet.

User Yatin
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