To find the surface area of a triangular prism, you need to calculate the area of the two triangular bases and the three rectangular faces.
Given your dimensions:
- Width (w): 4 cm
- Length (L): 11 cm (the length of the prism)
- Height (H): 3 cm (which can be interpreted as the height of the triangular base)
- There is an additional angle piece of 5 cm (this may refer to the length of one side of the triangle or possibly the slant height).
Assuming the given values correspond as follows:
- The triangular base is a right triangle with a height (H) of 3 cm and a base (w) of 4 cm, while the length of the prism is 11 cm.
Step 1: Area of the triangular base
The area \( A \) of a triangle is given by the formula: \[ A = \frac{1}{2} \times \text{base} \times \text{height} \] Substituting the values: \[ A = \frac{1}{2} \times 4 \text{ cm} \times 3 \text{ cm} = 6 \text{ cm}^2 \]
Step 2: Area of the two triangular bases
Since there are two triangular bases, the total area for the bases is: \[ \text{Area of bases} = 2 \times A = 2 \times 6 \text{ cm}^2 = 12 \text{ cm}^2 \]
Step 3: Area of the rectangular faces
The three rectangular faces consist of:
- One rectangle with dimensions of the base of the triangle (4 cm) and the length of the prism (11 cm).
- One rectangle with dimensions of the height of the triangle (3 cm) and the length of the prism (11 cm).
- One rectangle corresponding to the other side of the triangular base (which we can assume corresponds to the additional piece of 5 cm) and the length of the prism (11 cm).
Calculating each rectangular area:
-
Rectangle 1: \[ \text{Area} = 4 \text{ cm} \times 11 \text{ cm} = 44 \text{ cm}^2 \]
-
Rectangle 2: \[ \text{Area} = 3 \text{ cm} \times 11 \text{ cm} = 33 \text{ cm}^2 \]
-
Rectangle 3: Assuming the side with length 5 cm: \[ \text{Area} = 5 \text{ cm} \times 11 \text{ cm} = 55 \text{ cm}^2 \]
Step 4: Total surface area
Now sum the areas of the bases and the rectangular faces: \[ \text{Total surface area} = \text{Area of bases} + \text{Area of rectangles} \] \[ = 12 \text{ cm}^2 + 44 \text{ cm}^2 + 33 \text{ cm}^2 + 55 \text{ cm}^2 = 144 \text{ cm}^2 \]
Thus, the surface area of the triangular prism is: \[ \boxed{144} \text{ square centimeters} \]