Given:
Height, h = 4 cm
Base, = 6 cm
Length, L = 20 cm
To find the permieter of the base which is the is isosceles triangle, let's find the two equal sides using pythagorean theorem.
We have:
[tex]\begin{gathered} c=\sqrt[]{3^2+4^2} \\ \\ c=\sqrt[]{9+16} \\ \\ c=\sqrt[]{25} \\ \\ c=5 \end{gathered}[/tex]
thus, perimeter of the base is:
P = 5 + 5 + 6 = 16 cm
Thus, we have:
TSA =
[tex]\begin{gathered} TSA=(\frac{1}{2}\times6\times4)+(\frac{1}{2}\times6\times4)+(20\times5)+(20\times5)+(20\times6) \\ \\ \text{TSA}=12+12+100+100+120 \\ \\ \text{TSA}=344cm^2 \end{gathered}[/tex]
