Two equal triangles
2(1/2×b×h)
=2(1/2×8×10)
[tex] = 80 {cm}^{2} [/tex]
Three rectangles
=3(l×h)
=3(18×8)
=3(144)
[tex]432 {cm}^{2} [/tex]
Total Surface area
[tex]80 {cm}^{2} + 432 {cm}^{2} \\ 512 {cm}^{2} [/tex]
