To get the surface area of the prism given, we have to find the total area of the nets
We first split the nets into three and then find the areas
Lets us start with B
[tex]\text{Area of B=Area of a rectangle = length }\times Breadth[/tex]
Area of A and C are equal
so each of the areas is
[tex]\frac{1}{2}\times base\text{ }\times height[/tex]
But we can use a general formula for an equilateral traingular prism
[tex]\begin{gathered} =\frac{\sqrt[]{3^{}}\text{ }\times a^2}{2}+3(a\times h) \\ \text{where a=7} \\ h=18 \end{gathered}[/tex][tex]\text{Surface Area =}\frac{\sqrt[]{3^{}}\text{ }\times7^2}{2}+3(7\times18)[/tex]
Thus we have the total surface area to be approximately
[tex]\text{Surface area=}420.44ft^2[/tex]
