Answer:
SA = 480 cm²
Step-by-step explanation:
Surface area of the composite figure given in the picture = (Surface Area of the triangular prism on the top - area of the rectangular base) + (Surface area of the rectangular prism - Area of the rectangular base)
Surface area of the triangular prism = Area of the triangular bases + (perimeter of the base × Height)
= [tex]2(\frac{1}{2}\times 3\times 8)[/tex] + [(5 + 5 + 8)×12]
= 24 + 216
= 240 cm²
Area of the rectangular surface of the prism = 8 × 12 = 96 cm²
Surface area of the rectangular prism = 2(lb + bh + hl)
Here, l = Length, b = width and h = Height of the rectangular prism
= 2(8 × 12 + 12 × 6 + 6 ×8)
= 432 cm²
Surface area of the composite figure = (240 - 96) + (432 - 96)
= 144 + 336
= 480 cm²
