Can rectangles with a different area have the
same perimeter as this rectangle?
In this lesson you will learn that
rectangles can have the same
perimeter but different area by
building rectangles and organizing
information in a chart.
Let’s Review
Perimeter tells us the distance that goes around a
polygon.
Perimeter
Let’s Review
Width
Length
A Common Mistake
Mixing up area and perimeter.
Area
Perimeter
Core Lesson
Perimeter = 10
units
Perimeter = 10
units
Core Lesson
Area = 6 square
units
Area = 4 square
units
Core Lesson
Rectangle #1
Rectangle
#1
#2
#3
Rectangle #2
Rectangle #3
Perimeter
12 units
Length
1 unit
Width
5 units
Area
5 square units
12 units
12 units
4 units
2 units
3 units
3 units
8 square units
9 square units
Core Lesson
Rectangle #3
Rectangle #1
Rectangle #4
Rectangle #2
Core Lesson
Rectangle
#1
Perimeter
Length
Width
16 units
6 units
2 units
Area
12 square units
#2
16 units
7 units
#3
16 units
5 units
3 units
15 square units
#4
16 units
4 units
4 units
16 square units
1 unit
7 square units
In this lesson, you have learned that
rectangles can have the same
perimeter but different area by
building rectangles and organizing
information in a chart.
Guided Practice
Can rectangles with a different area have the same
perimeter as this rectangle?
Guided Practice
Rectangle
Perimeter
Length
Width
Area
Guided Practice
Rectangle #2
Rectangle #1
Rectangle
Perimeter
Length
Width
Area
#1
8 units
2 units
2 units
4 square units
#2
8 units
3 units
1 unit
3 square units
Extension Activities
Sally asked her father to build a fence around her backyard.
Her father bought 24 feet of fencing. Use square tiles to
make the rectangles and then make a chart to find the
biggest area for Sally’s backyard.
Extension Activities
Using square tiles, create as many rectangles as you can with
a perimeter of 36 units. Circle the rectangle with the biggest
area. Create a chart to show the different areas for the given
perimeter.
Extension Activities
This rectangle has a perimeter of 18 units. Fill in the
chart to show the possible areas.
Perimeter
18 units
18 units
18 units
18 units
Length
Width
Area
Extension Activities
Fill in this chart. You can use square tiles to help you
visualize the rectangles.
Perimeter
Length
20 units
7 units
20 units
Width
21 square units
1 unit
20 units
20 units
20 units
Area
20 square units
6 units
8 units
Quick Quiz
Here are some rectangles with a perimeter of 18 units.
Circle the rectangles with an area greater than 10 square
units.
Quick Quiz
Here are some rectangles with a perimeter of 12 units.
Circle the rectangles with an area greater than 7 square
units.