Use the image to answer the question.

An illustration shows a magnified, labeled figure of a two-part wing. The magnified two-part wing shows two similar pentagons, stacked in opposite directions upon each other, sharing a common base. The description of the top pentagon is as follows: The base is 1.4 meters, the bottom left, and right sides are smaller, and the top left and right sides are longer. A dashed line joining the top left and right vertices is labeled as 2.6 meters. The triangular region above this dashed line is shaded. The perpendicular distance from the top vertex to the dashed line is 0.3 meters, and from the dashed line to the base is 0.4 meters.

You are making a dragonfly kite. You want to cover the non-shaded area of the wings with shiny nylon. The dimensions of one pair of wings are shown. Decompose the figure into simple shapes. How many square meters of nylon will you need to cover the non-shaded area of one pair of wings?

(1 point)
Responses

3.98 square meters
3.98 square meters

2.38 square meters
2.38 square meters

1.19 square meters
1.19 square meters

1.99 square meters
1.99 square meters
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1 answer

To find the area of the non-shaded part of the wings, we first need to calculate the total area of the pentagon and then subtract the area of the shaded region.

  1. Total Area of the Pentagon: The area of a pentagon can be calculated by decomposing it into simpler shapes. However, since we are not given specific angles or details for calculation, we will use the provided dimensions.

    The total area (A) of a pentagon can often be derived, but based on the descriptions given:

    \[ A = \text{Area of base} \times \text{Average height} \]

    Where:

    • The base = 1.4 m
    • The height can be taken as the total height above the base, i.e., the sum of the height of the triangle and the perpendicular distance from the shaded area to the bottom.

    The total height from the base to the top vertex is: \[ \text{Height} = 0.3 m + 0.4 m = 0.7 m \]

    So the total area of one pentagon can be represented roughly, assuming it is effectively a shape whose area can be approximated: \[ A = 1.4 \times 0.7 = 0.98 \text{ square meters} \]

  2. Area of the Shaded Triangle: Now, we calculate the area of the triangular region (shaded):

    • Base of the triangle = 2.6 m (the dashed line)
    • Height of the triangle from top vertex to the dashed line = 0.3 m

    \[ \text{Area}{\text{shaded}} = \frac{1}{2} \times \text{Base} \times \text{Height} \] \[ \text{Area}{\text{shaded}} = \frac{1}{2} \times 2.6 \times 0.3 = 0.39 \text{ square meters} \]

  3. Area of the Non-shaded part: Subtract the shaded area from the total area of the pentagon to find the non-shaded area:

    \[ \text{Area}{\text{non-shaded}} = A - \text{Area}{\text{shaded}} \]

    \[ \text{Area}_{\text{non-shaded}} = 0.98 - 0.39 = 0.59 \text{ square meters} \]

  4. Total Area for One Pair of Wings: Since the dimensions given are for one pair of wings, we need to multiply by 2: \[ \text{Total non-shaded area}= 0.59 \times 2 = 1.18 \text{ square meters} \]

Out of the provided options, the closest match is: 1.19 square meters.