Exercise 41 Page 337

We want to calculate the surface area of a triangular pyramid. Let's see the given measurements of the pyramid.

The net is made up of triangles. We will calculate the area of each triangle separately, starting with the base. Let's substitute the measures of the base into the formula for the area of a triangle!

A=1/2 b* h

SubstituteII

b= 8, h= 6.9

A=1/2( 8)( 6.9)

Multiply

Multiply

A=27.6

The area of the base is 27.6 square meters. Now let's take a look at the sides. Note that sides of the pyramid are congruent triangles. This means that they have the same area. Let's substitute the measures of the sides into the formula for the area of a triangle!

A=1/2b* h

SubstituteII

b= 8, h= 10

A=1/2( 8)( 10)

Multiply

Multiply

A=40

We found that the area of one triangle is 40 square meters. Since the triangles are congruent, that means that the area of every triangle is 40 square meters. Now we have all the information that we need to find the total surface area of the triangular pyramid! Total Surface Area 27.6+ 40+ 40+ 40=147.6m^2 The total surface area of the triangular pyramid is 147.6 square meters.