Answer:
[tex]207yd^2[/tex]
Explanation:
Given that:
Side length of the base of the pyramid, b = 12 yd
Slant height, s = 11.5 yd
Height, h = 10.4 yd
Find the lateral surface area using the formula
[tex]LA=\frac{1}{2}Ps[/tex]
where P is the perimeter of the base.
First, find P.
[tex]\begin{gathered} P=12+12+12 \\ =36 \end{gathered}[/tex]
Substitute the values into the formula to find the lateral surface area.
[tex]\begin{gathered} LA=\frac{1}{2}\cdot36\cdot(11.5) \\ =207yd^2 \end{gathered}[/tex]
The lateral surface area of the equilateral triangular pyramid is 207 square yards.
