Question

SERIOUS HELP ONLY. (Use Special Right Triangles to Determine the Surface Area of a Regular Pyramid - Geometry).

Answer 1

Answer:

Option B

Step-by-step explanation:

a=side of square=8.4

h = height of the triangle = $1/2(8.4) sin 60 = 2.1\sqrt{3}$

Each triangle on 4 sides would be equilateral because one angle is 60 and isosceles.

Side of triangle s = 8.4

base area = $a^2 = 70.56$

Area of each equilateral triangle = $\sqrt{3} \frac{s^2}{4} =17.64\sqrt{3}$

Hence surface area = base area +4(area of each triangle)

$= 70.56+17.64\sqrt{3}(4)\\=192.769\\=192.8$ square yards

Hence option B is right answer