Question

Please help me with my math​

Answer 1

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)

= $2(\frac{1}{2}\times 3\times 8)$ + [(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