Using the net, we see that the square pyramid breaks down to 4 equivalent triangles and a square. We can use this formula to solve for the surface area:
Sa=A(square)+4A(triangle)
The formula for the area of a square is
A=lw
A=77
A=49mm²
The formula for the area of a triangle is:
A=1/2bh
A=1/2712.2
A=42.7mm²
Now that we have the individual areas of the shapes, we can solve for the surface area.
Sa=A(square)+4A(triangle)
Sa=49mm²+442.7mm²
Sa=49mm²+170.8mm²
Sa=219.8mm²
Answer=219.8mm²
ANSWER=A
