Glencoe Math: Course 1, Volume 2
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Glencoe Math: Course 1, Volume 2 View details
4. Surface Area of Triangular Prisms
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Exercise 1 Page 777

Add the area of the triangular bases to the area of the rectangular faces.

1152yd^2

Practice makes perfect

A triangular prism is a prism that has triangular bases. Let's take a look at the given diagram.

solid
We can use the net of this prism to find its surface area.
solid

The surface area of a triangular prism is the sum of the areas of the two triangular bases and the three rectangular faces. Let's calculate the area of the triangular bases and the area of the rectangular faces one at a time. Then we can add them together.

Triangular Bases

Looking at the net of this solid, for now let's think only about the triangular bases.
triangular bases
We can see that one of the triangular bases has a base of 51 yards and a height of 12 yards. Let's find its area by substituting these values into the formula for the area of a triangle.
A=1/2bh
A=1/2( 51)( 12)
â–Ľ
Evaluate right-hand side
A=1/2(612)
A=612/2
A=306
The area of one triangular base is 306 square yards. Because both of the triangular bases are exactly the same, we know that the area of the second triangular base is 306 square yards as well. Let's add them together! Area of the Triangular Bases 306+306= 612yd^2

Rectangular Faces

Now let's look at the rectangular faces.
rectangular faces
We can see that all three rectangular faces have a width of 5 yards. Also, their lengths are 37, 51, and 20 yards. Let's substitute the length and the width of each rectangle in the formula for the area of a rectangle to obtain their areas.
A=l w
Measures Substitute Evaluate
l= 37, w= 5 A= 37( 5) A= 185yd^2
l= 51, w= 5 A= 51( 5) A= 255yd^2
l= 20, w= 5 A= 20( 5) A= 100yd^2

Surface Area of the Prism

Finally, to get the surface area of the triangular prism, we add the area of both triangular bases and the area of the three rectangular faces. Surface Area of the Triangular Prism 612+ 185+ 255+ 100=1152yd^2