Use the image to answer the question.

An illustration shows a two-dimensional net of a triangular prism with all of its sides open and visible. The net appears as three horizontal parallelograms joined next to each other. All 4 sides of the middle parallelogram are drawn with dashed lines. The width of the parallelograms is 4 centimeters. The length of the middle parallelogram is 12 centimeters. Two right triangles adjoin the middle parallelogram on the top and bottom 12 centimeter sides, with their hypotenuse sides measuring 15 centimeters and the perpendicular sides measuring 9 centimeters. Right angles are shown at the intersection of the perpendicular sides and the base sides of the triangles.

What is the surface area of the triangular prism whose net is shown?

(1 point)
Responses

108 cm2
108 cm squared

252 cm2
252 cm squared

216 cm2
216 cm squared

198 cm2

1 answer

To find the surface area of the triangular prism represented by the net, we need to consider the areas of the different components of the net:

  1. Area of the three parallelograms: Each parallelogram has a width of 4 cm and a length of 12 cm. The area of one parallelogram is calculated as: \[ \text{Area of one parallelogram} = \text{Width} \times \text{Length} = 4 , \text{cm} \times 12 , \text{cm} = 48 , \text{cm}^2 \] Since there are three parallelograms: \[ \text{Total area of parallelograms} = 3 \times 48 , \text{cm}^2 = 144 , \text{cm}^2 \]

  2. Area of the two triangular bases: Each right triangle has base and height measuring 9 cm (height) and 12 cm (base). The area of one triangle is calculated as: \[ \text{Area of one triangle} = \frac{1}{2} \times \text{Base} \times \text{Height} = \frac{1}{2} \times 12 , \text{cm} \times 9 , \text{cm} = \frac{1}{2} \times 108 , \text{cm}^2 = 54 , \text{cm}^2 \] Therefore, the total area of the two triangles is: \[ \text{Total area of triangles} = 2 \times 54 , \text{cm}^2 = 108 , \text{cm}^2 \]

  3. Total surface area of the triangular prism: To find the total surface area, we add the area of the parallelograms and the area of the triangles: \[ \text{Total Surface Area} = \text{Area of parallelograms} + \text{Area of triangles} = 144 , \text{cm}^2 + 108 , \text{cm}^2 = 252 , \text{cm}^2 \]

Thus, the surface area of the triangular prism is 252 cm².

The correct response is: 252 cm²