We will calculate the total surface area;
The total surface area is given by
[tex]\text{TSA}=a(a+\sqrt[]{a^2+4h^2})[/tex]where a is the base-length and h is the height
From the fig.
a=6cm
h=15cm
substituting into the formula;
[tex]\text{TSA}=6(6+\sqrt[]{6^2+4(15)^2})[/tex]Then evaluate;
[tex]\text{TSA}=6(6+\sqrt[]{36+900}[/tex][tex]=6(6+\sqrt[]{936)}[/tex][tex]=6(6+30.6)[/tex]=6(36.6)
=219.6 cm²
A gold foil of area 219.6 cm² is needed
