Decide mentally which expression has a greater value.
or
or
or
or
18.2
Activity
A cube has an edge length of 5 units.
Draw a net for this cube on graph paper. Label its sides with measurements.
What is the shape of each face?
What is the area of each face?
What is the surface area of this cube?
What is the volume of this cube?
A second cube has an edge length of 17 units.
Sketch a net for this cube. Label its sides with measurements.
Explain why the area of each face of this cube is square units.
Write an expression for the surface area, in square units.
Write an expression for the volume, in cubic units.
18.3
Activity
A cube has an edge length of .
Draw a net for the cube.
Write an expression for the area of each face. Label each face with its area.
Write an expression for the surface area.
Write an expression for the volume.
Student Lesson Summary
The volume of a cube with an edge length of is .
A cube has 6 faces that are all identical squares. For a cube with an edge length of , the area of each square face is . This means that the surface area of the cube is .