Calculating the Area of a Rectangle Using Square Units

This lesson teaches how to describe the area of a plane figure using square units. It begins with a review of plane figures and their attributes, then introduces the concept of area as a measurement distinct from perimeter. The lesson explains that area is the space within a closed shape and is measured in square units. It emphasizes that only closed shapes have measurable areas and demonstrates how square units are used to calculate the area of a rectangle. The lesson concludes with practical examples of using square units to determine area.

What is a plane figure?

• A three-dimensional object

• A two-dimensional shape

• A line segment

• A point on a graph

Which of the following is NOT an attribute of a plane figure?

• Rectangle

• Volume

• Closed

• Flat

What is the main difference between area and perimeter?

• Area is the space inside a shape, while perimeter is the length of the boundary.

• Area is the length of the boundary, while perimeter is the space inside a shape.

• Area and perimeter are the same.

• Area is measured in linear units, while perimeter is measured in square units.

Why can't we measure the area of an open shape?

• Because it is not flat

• Because it has no width

• Because it has no length

• Because it is not closed

What is a square unit?

• A square with each side measuring one unit

• A unit of volume

• A unit of length

• A triangle with each side measuring one unit