Answer:
• lateral area: 36√3 square units
• total surface area: (36 +36√3) square units
Step-by-step explanation:
The area of an equilateral triangle of side length s is given by ...
A = (√3)/4·s^2
Your pyramid has four (4) such faces of side length 6 units, so the total (lateral) area of the triangular faces is ...
LA = √3·(6 units)^2 = 36√3 square units
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Of course the area of the square base is simply the square of its edge length, so is ...
A = (6 units)^2 = 36 square units
That means the total surface area, the lateral area plus the base area, is ...
(36 +36√3) square units