What is the volume of this prism?

Start by finding the area of the base. Show your work on paper, then enter your answer on Zearn.
A prism with a pentagonal base decomposed into a rectangle with dimensions 10 cm by 4 cm, and a triangle with a height of 6 cm and a base along the 10 cm side of the rectangle. The distance between the identical bases is labeled 5 cm.
Area of the base, B Height of the prism, h Volume
V = B · h
cm
2
? cm ? cm
3

1 answer

To find the volume of the prism, we first need to calculate the area of the base, which consists of a rectangle and a triangle.

Step 1: Find the area of the rectangle.

The formula for the area of a rectangle is:

\[ \text{Area}_{\text{rectangle}} = \text{length} \times \text{width} \]

Given the dimensions of the rectangle:

  • Length = 10 cm
  • Width = 4 cm

Calculating the area:

\[ \text{Area}_{\text{rectangle}} = 10 , \text{cm} \times 4 , \text{cm} = 40 , \text{cm}^2 \]

Step 2: Find the area of the triangle.

The formula for the area of a triangle is:

\[ \text{Area}_{\text{triangle}} = \frac{1}{2} \times \text{base} \times \text{height} \]

For the triangle:

  • Base = 10 cm (along the side of the rectangle)
  • Height = 6 cm

Calculating the area:

\[ \text{Area}_{\text{triangle}} = \frac{1}{2} \times 10 , \text{cm} \times 6 , \text{cm} = \frac{1}{2} \times 60 = 30 , \text{cm}^2 \]

Step 3: Find the total area of the base.

The total area of the base \( B \) is the sum of the area of the rectangle and the area of the triangle:

\[ B = \text{Area}{\text{rectangle}} + \text{Area}{\text{triangle}} = 40 , \text{cm}^2 + 30 , \text{cm}^2 = 70 , \text{cm}^2 \]

Step 4: Find the height of the prism.

The height of the prism \( h \) is given as 5 cm.

Step 5: Calculate the volume of the prism.

The volume \( V \) of the prism is calculated using the formula:

\[ V = B \times h \]

Substituting the values we found:

\[ V = 70 , \text{cm}^2 \times 5 , \text{cm} = 350 , \text{cm}^3 \]

Summary:

  • Area of the base, \( B = 70 , \text{cm}^2 \)
  • Height of the prism, \( h = 5 , \text{cm} \)
  • Volume, \( V = 350 , \text{cm}^3 \)

The final answer to enter is:

  • Volume = 350 cm³.