Answer:
The total surface area of this square pyramid is [tex]297\ mm^{2}[/tex]
Step-by-step explanation:
we know that
The surface area of a square pyramid is equal to
[tex]SA=b^{2} +4[\frac{1}{2}(b)(h)][/tex]
we have
[tex]b=9\ mm[/tex] ----> the length side of the square base
[tex]h=12\ mm[/tex] ----> the height of the triangular faces
substitute the values
[tex]SA=9^{2} +4[\frac{1}{2}(9)(12)]=297\ mm^{2}[/tex]
