What is the surface area of a square pyramid where the base edge is 8 ft. and the slant height is 16 ft.?(1 point) Responses 128 ft.2 128 ft. squared 320 ft.2 320 ft. squared 256 ft.2 256 ft. squared 512 ft.2

1 answer

To find the surface area of a square pyramid, you can use the formula:

\[ \text{Surface Area} = \text{Base Area} + \text{Lateral Area} \]

  1. Calculate the base area: The base of the pyramid is a square with a side length of 8 ft.

    \[ \text{Base Area} = \text{side}^2 = 8 , \text{ft} \times 8 , \text{ft} = 64 , \text{ft}^2 \]

  2. Calculate the lateral area: The lateral area of a square pyramid is given by:

    \[ \text{Lateral Area} = \frac{1}{2} \times \text{Perimeter of the base} \times \text{slant height} \]

    The perimeter of the base is:

    \[ \text{Perimeter} = 4 \times \text{side} = 4 \times 8 , \text{ft} = 32 , \text{ft} \]

    Now substituting the values into the lateral area formula:

    \[ \text{Lateral Area} = \frac{1}{2} \times 32 , \text{ft} \times 16 , \text{ft} = 256 , \text{ft}^2 \]

  3. Total surface area: Now we can sum the base area and lateral area to find the total surface area:

    \[ \text{Surface Area} = \text{Base Area} + \text{Lateral Area} = 64 , \text{ft}^2 + 256 , \text{ft}^2 = 320 , \text{ft}^2 \]

Thus, the surface area of the square pyramid is 320 ft² (or 320 ft. squared).