The surface area of this triangular pyramid, whose base and lateral faces are congruent equilateral triangles, is __ square inches.
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Answer:
The surface area is equal to [tex]390\ in^{2}[/tex]
Step-by-step explanation:
The surface area of the triangular pyramid is equal to the area of its four triangular faces
so
In this problem
[tex]SA=4[\frac{1}{2}(b)(h)][/tex]
we have
[tex]b=15\ in[/tex]
[tex]h=13\ in[/tex]
substitute the values
[tex]SA=4[\frac{1}{2}(15)(13)]=390\ in^{2}[/tex]