Answer:
144m²
Step-by-step explanation:
The the model made by Marie is attached in the diagram below.
The square pyramid model that Marie has in mind of building has 4 congruent triangular faces on the four sides of the square pyramid, and 1 base square. Therefore the surface area of the square pyramid = area of the square + area of 4 triangles = b² + 4(1/2*b*h)
Given that b = 8, and h = 5, we have:
Surface area = 8² + 4(1/2*8*5)
= 64 + 4(20)
= 64 + 80
SA of the square pyramid = 144m²
