Question

The surface area of this triangular pyramid, whose base and lateral faces are congruent equilateral triangles, is __ square inches.

Answer 1

Answer:

390

Step-by-step explanation:

Answer 2

Answer:

The surface area is equal to $390\ in^{2}$

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

$SA=4[\frac{1}{2}(b)(h)]$

we have

$b=15\ in$

$h=13\ in$

substitute the values

$SA=4[\frac{1}{2}(15)(13)]=390\ in^{2}$