Question

What is the surface area of the figure a:441 b:301 c:252 d:175

Answer 1

Answer:

  d.  175 square inches

Step-by-step explanation:

If we assume the base is square and all triangular faces are congruent, then the lateral area of the figure is that of four triangles. Each triangle has an area that is half the product of its base and height:

  A = (1/2)bh = (1/2)(7 in)(9 in) = 31.5 in^2

The area of the square base is the product of its length and width, both of which are 7 in.

  A = lw = (7 in)(7 in) = 49 in^2

So, the total surface area is that of the base plus the four sides:

  surface area = (49 in^2) + 4(31.5 in^2) = 175 in^2 . . . . . matches choice D