A triangular pyramid has a base shaped like an equilateral triangle. The legs of the equilateral triangle are all 20 inches long, and the height of the equilateral triangle is 17.3 inches. The pyramid's slant height is 13 inches. What is its surface area?

Surface area of pyramid with base equilateral triangle is square inches

Step-by-step explanation:

Recall the following result:

The total surface area(S) of a regular pyramid is given by,

                                      ...... (1)

Here, p represents the perimeter of the base , the slant height and B the base area of the pyramid.

From the given information:

Side of equilateral triangle = 20 inches

Slant height of the pyramid() = 13 inches.

First find the perimeter and Area of the base pyramid.

Perimeter of equilateral triangle(p) =

                                                          =

Area of equilateral triangle(B) =

                                                 =  square inches.

Substitute the above values in equation (1) as shown below:

square inches

Hence, the surface area of pyramid with base equilateral triangle is square inches.

ca = ec

cpctc makes it so that corresponding parts of the triangle you proved to be equal are equal, the other options aren't part of the part of the triangles you proved to be equal.

answer is (b.

164 ft2)

a base  

18

b base  

7

h height  

8