Surface Area of Rectangular Prisms
Surface area is the total area of all faces of a 3D shape. For a rectangular prism, we add the areas of all six rectangular faces to find the total surface area.
What You Need to Know
Key Concept Diagram
A rectangular prism has 6 faces: top, bottom, front, back, left, and right
Opposite faces are identical, so there are 3 pairs of faces
SA = 2(lw + lh + wh) where l = length, w = width, h = height
Surface area is measured in square units: cm², m²
Key Vocabulary
Surface area
The total area of all outer faces of a 3D shape
Face
A flat surface of a 3D shape
Net
A 2D pattern that can be folded to form a 3D shape
Rectangular prism
A 3D shape with 6 rectangular faces, also called a cuboid
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
A rectangular prism has length 4 cm, width 3 cm, height 2 cm. What is the area of the top face?
Question 2
A box has l = 5 cm, w = 2 cm, h = 3 cm. How many pairs of identical faces does it have?
Question 3
Calculate the surface area of a rectangular prism with l = 3 cm, w = 2 cm, h = 4 cm.
Key Concepts Summary
- ●A rectangular prism has 6 faces: top, bottom, front, back, left, and right
- ●Opposite faces are identical, so there are 3 pairs of faces
- ●SA = 2(lw + lh + wh) where l = length, w = width, h = height
- ●Surface area is measured in square units: cm², m²