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Ian wraps a gift box in the shape of a square pyramid. The figure below shows a netfor the gift box.

Ian wraps a gift box in the shape of a square pyramid. The figure below shows a netfor-example-1
User Sard
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1 Answer

27 votes
27 votes

Since we want to know how much wrapping paper he used in square centimeters, we want to figure the total surface area of the gift box.

Since it is a square pyramid, the triangles of the sides are all congruent, and the base is a square.

So, tha area of the square base is the multiplication of its sides, which are equal:


A_s=9.3\cdot9.3=86.49

For the triangles, we can clauclate the area of one of them and multiply by 4 to get the area of all. The area of a triangle is its base multiplyed by its height divided by 2. The height is given and the base is the same as the square sides. So the area of 1 triangle is:


A_t=(9.3\cdot9.6)/(2)=44.64

So, the tota area is the area of the square plus 4 times the area of one triangle:


A=86.49+4\cdot44.64=86.49+178.56=265.05

This is already in the proper unit, so the area is 265.05 cm².

User Zachbugay
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