Question

I need help with these 2 questions.

Answer 1

Answer:

Step-by-step explanation:

6). Surface area of a triangular prism = Area of the triangular bases + (Perimeter of the triangular base)×height

Area of one triangular base = $\frac{1}{2}(\text{Base})(\text{Height})$

                                              = $\frac{1}{2}\times 4\times 3$

                                              = 6 km²

Perimeter of the triangular base = (4 + 3 + 5)

                                                      = 12 km

Height of the triangular prism = 7 km

Surface area of the given triangular prism = 2(6) + (12)(7)

                                                                      = 12 + 84

                                                                      = 96 km²

7). Surface area of a rectangular prism = 2(lb + bh + hl)

Here, l = Length, b = Width and h = Height

By substituting the values from the given question,

l = 9 in, b = 9 in, h = 4 in

Surface area of the rectangular prism = 2(9×9 + 9×4 + 4×9)

                                                               = 2(81 + 36 + 36)

                                                               = 2(153)

                                                               = 306 in²