1. 3rd Grade Math Module 7 Lesson 14
engageny
3rd Grade Math
Module 7 Lesson 14

2. I can determine the perimeter of regular polygons and rectangles.
Lesson 14 Learning Goal
I can determine the perimeter of regular polygons and rectangles.

3. Say the multiplication sentence
Lesson 14
I can determine the perimeter of
regular polygons and rectangles.
Count by sevens to 70.
7, 14, 21, 28, 35, 42, 49, 56, 63, 70 1
seven 2
sevens 3
sevens 4
sevens 5
sevens 6
sevens 7
sevens 8
sevens 9
sevens 10
sevens
Say the multiplication sentence
Equivalent Counting with Units of Seven

4. Lesson 14
I can determine the perimeter of
regular polygons and rectangles.
A rectangular sheep pen measures 9 meters long and 5 meters wide. The perimeter of the cow pen is double the perimeter of the sheep pen. What is the perimeter of the cow pen?
Application Problem

5. The perimeter of the cow pen is 56 meters.
Lesson 14
I can determine the perimeter of
regular polygons and rectangles.
A rectangular sheep pen measures 9 meters long and 5 meters wide. The perimeter of the cow pen is double the perimeter of the sheep pen. What is the perimeter of the cow pen?
9 m
p =
p = 28 meters
c =
c = 56 meters
5 m
5 m
Sheep pen
9 m
The perimeter of the cow pen is 56 meters.
Application Problem

6. Lesson 14 This shape is a rectangle.
I can determine the perimeter of
regular polygons and rectangles.
This shape is a rectangle.
What are the missing side lengths?
9 cm
6 cm
6 cm
9 cm
Concept Development

7. Lesson 14 Write a number sentence that finds
I can determine the perimeter of
regular polygons and rectangles.
Write a number sentence that finds
the perimeter of the rectangle.
9 cm
6 cm
6 cm
9 cm
= 30 cm
Concept Development

8. Lesson 14 Write a number sentence that finds
I can determine the perimeter of
regular polygons and rectangles.
Write a number sentence that finds
the perimeter of the rectangle.
10 in
8 in
= 36 in
Concept Development

9. Lesson 14 Write a number sentence that finds
I can determine the perimeter of
regular polygons and rectangles.
Write a number sentence that finds
the perimeter of the rectangle.
14 cm
36 cm
= 100 cm
Concept Development

10. Lesson 14 This shape is a regular hexagon.
I can determine the perimeter of
regular polygons and rectangles.
This shape is a regular hexagon.
What are the missing side lengths?
3 cm
3 cm
3 cm
3 cm
3 cm
3 cm
Concept Development

11. Lesson 14 Write a number sentence that finds
I can determine the perimeter of
regular polygons and rectangles.
Write a number sentence that finds
the perimeter of the hexagon.
3 cm
3 cm
3 cm
3 cm
3 cm
3 cm
= 18 cm
Concept Development

12. Lesson 14 What multiplication sentence finds
I can determine the perimeter of
regular polygons and rectangles.
What multiplication sentence finds
the perimeter of the hexagon?
3 cm
3 cm
3 cm
3 cm
3 cm
3 cm
= 18 cm
6 x 3 = 18 cm
Concept Development

13. Lesson 14 This shape is a regular pentagon.
I can determine the perimeter of
regular polygons and rectangles.
This shape is a regular pentagon.
What are the missing side lengths?
7 in
7 in
7 in
7 in
7 in
Concept Development

14. Lesson 14 Write a number sentence that finds
I can determine the perimeter of
regular polygons and rectangles.
Write a number sentence that finds
the perimeter of the pentagon.
7 in
7 in
7 in
7 in
7 in
= 35 inches
5 x 7 = 35 inches
Concept Development

15. Lesson 14 Which method is more efficient
I can determine the perimeter of
regular polygons and rectangles.
Which method is more efficient
for finding the perimeter of a regular polygon,
adding or multiplying?
7 in
7 in
7 in
7 in
7 in
= 35 inches
5 x 7 = 35 inches
Concept Development

16. Lesson 14 This shape is a regular triangle.
I can determine the perimeter of
regular polygons and rectangles.
This shape is a regular triangle.
What are the missing side lengths?
17 cm
17 cm
17 cm
Concept Development

17. Lesson 14 Write a number sentence that finds
I can determine the perimeter of
regular polygons and rectangles.
Write a number sentence that finds
the perimeter of the pentagon.
17 cm
17 cm
17 cm
= 51 cm
3 x 17 = 51 cm
Concept Development