Given:
Side length of base = 8
Slant height = 6
To find:
The surface area of the square pyramid.
Solution:
Surface area:

where A is the area of base
p is the perimeter of base
s is the slant height
Area of base (A) = 8 × 8
= 64
Perimeter of base(P) = 4 × 8
= 32
Substitute these in the formula:



The surface area of the square pyramid is 160 unit².
Answer:
18 is the answer to your question.
Just doing this to get points... :(
72,429 rounded to the nearest ten-thousands is 70,000.