Answer:
lateral area = 1892.1 m²
Explanation:
The lateral surface area of the square based pyramid is required.
lateral surface area = 1/2 × perimeter × slant height
we have to find the slant height using Pythagoras theorem
base = 35
height = 20.6
slant height² = 17.5² + 20.6²
slant height² = 306.25 + 424.36
slant height² = 730.61
slant height = √730.61
slant height = 27.0297983714
slant height ≈ 27.03 m
lateral area = 1/2 × perimeter × slant height
lateral area = 1/2 × 35 × 4 × 27.03
lateral area = 3784.200/2
lateral area = 1892.1 m²