Use the image to answer the question.

A composite shape is drawn using a rectangle and 2 triangles. A horizontally aligned rectangle is 9 centimeters long and 3 centimeters wide. A right triangle facing upward adjoins the rectangle on the left side marked 3 centimeters. A right triangle facing downward adjoins the rectangle on the right side. The base leg of both triangles measures 2 centimeters.

Hector designs the piece of jewelry shown below. All lengths are marked in centimeters. What is the total area of the piece of jewelry?

(1 point)
Responses

33 square centimeters
33 square centimeters

27 square centimeters
27 square centimeters

39 square centimeters
39 square centimeters

30 square centimeters

1 answer

To find the total area of the composite shape made of a rectangle and two triangles, we first need to calculate the area of each component separately.

  1. Area of the Rectangle: The formula for the area of a rectangle is: \[ \text{Area} = \text{length} \times \text{width} \] Given that the rectangle is 9 cm long and 3 cm wide: \[ \text{Area of Rectangle} = 9 , \text{cm} \times 3 , \text{cm} = 27 , \text{square centimeters} \]

  2. Area of the Triangles: Each triangle is a right triangle with a base of 2 cm and a height of 3 cm (the height of the rectangle). The area of a right triangle is given by: \[ \text{Area} = \frac{1}{2} \times \text{base} \times \text{height} \] For one triangle: \[ \text{Area of one triangle} = \frac{1}{2} \times 2 , \text{cm} \times 3 , \text{cm} = 3 , \text{square centimeters} \]

    Since there are two triangles: \[ \text{Area of two triangles} = 2 \times 3 , \text{square centimeters} = 6 , \text{square centimeters} \]

  3. Total Area of the Composite Shape: Now we can find the total area by adding the areas of the rectangle and the triangles: \[ \text{Total Area} = \text{Area of Rectangle} + \text{Area of two triangles} = 27 , \text{cm}^2 + 6 , \text{cm}^2 = 33 , \text{square centimeters} \]

Thus, the total area of the piece of jewelry is 33 square centimeters.