Perimeter & Area of Composite Shapes

Vocabulary flashcards that review the essential terms and strategies for calculating the perimeter and area of a composite L-shaped figure.

Perimeter

The total distance around the outside of a shape, found by adding together all its side lengths.

Area

The amount of surface inside a shape, measured in square units.

Composite Shape

A figure made by combining two or more simple shapes, such as rectangles.

L-shaped Figure

A common composite shape resembling the letter “L,” created by joining two rectangles.

Missing Side Length

A side measurement not given directly that must be deduced from the known sides of the figure.

Length (rectangle)

One of a rectangle’s perpendicular dimensions, often the longer side used in the area formula.

Width (rectangle)

The other perpendicular dimension of a rectangle; multiplied by the length to find area.

Rectangle Area Formula

Area = length × width.

Square Unit

A unit of area equal to a square with sides one unit long, such as a square foot (ft²).

Decomposition (area)

Breaking a composite figure into simpler shapes to make area calculations easier.

Perimeter Strategy

Add all side lengths—after finding any unknown sides—to obtain the total perimeter.

Total Area Strategy

Find the area of each simple shape in a composite figure and add those areas together.

Vertical Side

A side that runs up and down in a diagram or shape.

Horizontal Side

A side that runs left to right in a diagram or shape.

Square Feet (ft²)

A unit for measuring area when side lengths are in feet; represents a square one foot on each side.