unit 6 lesson 5
surface area of rectangular prisms practice
use the image to answer the question
9cm,5cm,8cm
what is the surface area of the rectangular prism?
_ cm^2
To find the surface area of a rectangular prism, you need to calculate the area of each of the six faces and then add them all together.
The rectangular prism has 6 faces: 2 rectangular faces with dimensions 9cm by 5cm, 2 rectangular faces with dimensions 9cm by 8cm, and 2 rectangular faces with dimensions 5cm by 8cm.
Calculating the area of each face:
1. The two rectangular faces with dimensions 9cm by 5cm have areas of 9cm x 5cm = 45cm^2 each. The total area for these two faces combined is 2 x 45cm^2 = 90cm^2.
2. The two rectangular faces with dimensions 9cm by 8cm have areas of 9cm x 8cm = 72cm^2 each. The total area for these two faces combined is 2 x 72cm^2 = 144cm^2.
3. The two rectangular faces with dimensions 5cm by 8cm have areas of 5cm x 8cm = 40cm^2 each. The total area for these two faces combined is 2 x 40cm^2 = 80cm^2.
Adding all the areas together:
90cm^2 + 144cm^2 + 80cm^2 = 314cm^2
Therefore, the surface area of the rectangular prism is 314 cm^2.