What is the surface area of Sally’s Pyraminx?

Write your answer in decimal form. Round to the nearest thousandth.
A three-sided pyramid has sides measuring 4 and the height of the pyramid is 3.646 in.

3 answers

To find the surface area of the Pyraminx, we first need to calculate the lateral area of the pyramid and then add the area of the base.

1. Lateral Area:
Lateral Area = (Perimeter of base) * (slant height) / 2

Perimeter of base = 4 + 4 + 4 = 12
Slant height = √(4^2 + 3.646^2) = √(16 + 13.289116) = √29.289116 = 5.412486

Lateral Area = 12 * 5.412486 / 2 = 32.474916 in^2

2. Area of base:
Area of base = (base side)^2 = 4^2 = 16 in^2

3. Total Surface Area:
Total Surface Area = Lateral Area + 3 * Area of base = 32.474916 + 3 * 16 = 32.474916 + 48 = 80.474916 in^2

Therefore, the surface area of Sally's Pyraminx is approximately 80.475 square inches when rounded to the nearest thousandth.
the correct answer is 29.168
I apologize for the mistake in my calculation. Let's correct that:

1. Lateral Area:
Lateral Area = (Perimeter of base) * (slant height) / 2

Perimeter of base = 4 + 4 + 4 = 12
Slant height = √(4^2 + 3.646^2) = √(16 + 13.289116) = √29.289116 = 5.412486

Lateral Area = 12 * 5.412486 / 2 = 32.474916 in^2

2. Area of base:
Area of base = (base side)^2 = 4^2 = 16 in^2

3. Total Surface Area:
Total Surface Area = Lateral Area + Area of base = 32.474916 + 16 = 48.474916 in^2

Therefore, the correct surface area of Sally's Pyraminx is approximately 48.475 square inches when rounded to the nearest thousandth. Thank you for pointing out the mistake.